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    Wyświetlanie 1-97 z 97
    Tytuł:
    De-Lubrication Behavior Of Novel EBS Based Admixed Lubricant In Aluminum P/M Alloy
    Zachowanie nowego lubrykantu na bazie EBS w trakcie spiekania proszku stopu aluminium
    Autorzy:
    Oh, M. C.
    Seok, H.
    Kim, H. J.
    Ahn, B.
    Powiązania:
    https://bibliotekanauki.pl/articles/354258.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    admixed lubricant
    compaction pressure
    powder metallurgy
    sintering
    Al-Cu-Mg alloy
    lubrykant
    zagęszczanie
    metalurgia proszków
    spiekanie
    stop Al-Cu-Mg
    Opis:
    The objective of the present research is to develop a novel lubricant for Al-Cu-Mg P/M alloy and to address the effects of the lubricant and compaction pressure on sintered properties. A lubricant mixture consisting of Ethylene Bis Stearamide, Zn-Stearate, and fatty acid was newly developed in this study, and the de-lubrication behavior was compared with that of other commercial lubricants, such as Ethylene Bis Stearamide, Zn-Stearate, and Al-Stearate. Density and transverse rupture strength of sintered materials with each lubricant were examined, respectively. The microstructural analysis was conducted using optical microscope.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1427-1431
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    User requirements supporting the safe navigation in Korean Coast
    Autorzy:
    Jeong, J.S.
    Jeong, J.
    Kim, H.J.
    Kim, S. Y.
    Powiązania:
    https://bibliotekanauki.pl/articles/320412.pdf
    Data publikacji:
    2013
    Wydawca:
    Polskie Forum Nawigacyjne
    Tematy:
    user requirements
    user needs
    e-navigation
    safe navigation
    navigational information
    Opis:
    This research aims at investigating the user requirements at the service level for safe navigation system, following e-navigation strategy implementation plan. The user requirements is surveyed to collect real-time navigational information and then to find out services through the presentation of the collected information. To provide the information on user needs for the system developer, a questionnaire survey has been made. Based on this surveys, this research investigated which navigational information is with higher priority for the safe navigation during ship operation by bridge team in harbour and in coastal and confined.
    W artykule przedstawiono wyniki badań wymagań użytkownika związanych z poziomem bezpieczeństwa nawigacji, stosownie do strategii wprowadzania e-nawigacji. Badano oczekiwania użytkowników odnośnie informacji nawigacyjnej dostarczanej w czasie rzeczywistym oraz sposobu jej prezentacji metodą ankietową. Wykonano przegląd kwestionariuszy dla ustalenia informacji o potrzebach użytkownika z myślą o projektantach systemów. Na bazie opisywanych badań ustalono, jakie informacje nawigacyjne cechują się najwyższym priorytetem w opinii użytkowników, zarówno w warunkach żeglugi przybrzeżnej, jak i w porcie lub akwenie ograniczonym.
    Źródło:
    Annual of Navigation; 2013, 20; 37-48
    1640-8632
    Pojawia się w:
    Annual of Navigation
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Milling Time Parameter on the Microstructure and the Thermoelectric Properties of n-Type Bi2Te2.7Se0.3 Alloys
    Autorzy:
    Sharief, P.
    Madavali, B.
    Koo, J. M.
    Kim, H. J.
    Hong, S.
    Hong, S.-J.
    Powiązania:
    https://bibliotekanauki.pl/articles/354418.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    ball milling
    milling time
    microstructure
    thermoelectric properties
    ZT
    Opis:
    Nanostructured thermoelectric materials receiving great attention for its high thermoelectric performance. In this research, nanostructured n-type Bi2 Te2.7 Se0.3 alloys have prepared using high energy ball milling and followed by spark plasma sintering. Also, we have varied ball milling time to investigate milling time parameter on the thermoelectric properties of n-type Bi2 Te2.7 Se0.3 powder. The powders were discrete at 10 min milling and later particles tend to agglomerate at higher milling time due to cold welding. The bulk fracture surface display multi-scale grains where small grains intersperse in between large grains. The maximum Seebeck coefficient value was obtained at 20-min milling time due to their lower carrier density. The κ values were decreased with increasing milling time due to the decreasing trend observed in their κL values. The highest ZT of 0.7 at 350 K was observed for 30-min milling time which was ascribed to its lower thermal conductivity. The Vickers hardness values also greatly improved due to their fine microstructure.
    Źródło:
    Archives of Metallurgy and Materials; 2019, 64, 2; 585-590
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Microstructure and Magnetic Properties of NdFeB Sintered Magnets Diffusion-Treated with Cu/Al Mixed Dyco Alloy-Powder
    Autorzy:
    Lee, M.-W.
    Bae, K.-H.
    Lee, S.-R.
    Kim, H.-J.
    Jang, T.-S.
    Powiązania:
    https://bibliotekanauki.pl/articles/353351.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Nd-Fe-B sintered magnets
    grain boundary diffusion process
    low melting point element
    DyCo alloy-powder diffusion
    Opis:
    We investigated the microstructural and magnetic property changes of DyCo, Cu + DyCo, and Al + DyCo diffusion-treated NdFeB sintered magnets. The coercivity of all diffusion treated magnet was increased at 880ºC of 1st post annealing(PA), by 6.1 kOe in Cu and 7.0 kOe in Al mixed DyCo coated magnets, whereas this increment was found to be relatively low (3.9 kOe) in the magnet coated with DyCo only. The diffusivity and diffusion depth of Dy were increased in those magnets which were treated with Cu or Al mixed DyCo, mainly due to comparatively easy diffusion path provided by Cu and Al because of their solubility with Ndrich grain boundary phase. The formation of Cu/Al-rich grain boundary phase might have enhanced the diffusivity of Dy-atoms. Moreover, relatively a large number of Dy atoms reached into the magnet and mostly segregated at the interface of Nd2 Fe14 B and grain boundary phases covering Nd2 Fe14 B grains so that the core-shell type structures were developed. The formation of highly anisotropic (Nd, Dy)2Fe14B phase layer, which acted as the shell in the core-shell type structure so as to prevent the reverse domain movement, was the cause of enhancing the coercivity of diffusion treated NdFeB magnets. Segregation of cobalt in Nd-rich TJP followed by the formation of Co-rich phase was beneficial for the coercivity enhancement, resulting in the stabilization of the metastable c-Nd2O3 phase.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1263-1266
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect Of DyMn Alloy-Powder Addition On Microstructure And Magnetic Properties Of NdFeB Sintered Magnets
    Wpływ dodatku proszku DyMn na mikrostrukturę i właściwości magnetyczne spiekanych magnesów NdFeB
    Autorzy:
    Lee, M.-W.
    Dhakal, D. R.
    Kim, T. H.
    Lee, S. R.
    Kim, H. J.
    Jang, T. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/357010.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Nd-Fe-B sintered magnets
    DyMn-alloy powder
    coercivity
    low melting point element
    magnesy spiekane
    proszek DyMn
    koercja
    elementy o niskiej temperaturze topnienia
    Opis:
    Micostructural change and corresponding effect on coercivity of a NdFeB sintered magnet mixed with small amount of DyMn powder was investigated. In the sintered magnet mixed with the DyMn alloy-powder Dy-rich shell was formed at outer layer of the main grains, while Mn was mostly concentrated at Nd-rich triple junction phase (TJP), lowering melting temperature of the Nd-rich phase that eventually improved the microstructural characteristics of the gain boundary phase. The coercivity of a magnet increased more than 3.5 kOe by the mixing of the DyMn alloy-powder.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1407-1409
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Graphite Nanosheet Exfoliation From Graphite Flakes Through Functionalization Using Phthalic Acid
    Złuszczanie nanoarkuszy grafitu z płatków grafitu przy użyciu kwasu ftalowego
    Autorzy:
    Kim, J. H.
    Lee, J. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/351457.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    exfoliation
    graphite nanosheet
    functionalization
    grafting molecule
    Friedel-Crafts acylation
    złuszczanie
    nanoarkusz grafitu
    funkcjonalizacja
    kwas ftalowy
    acylowanie Friedela-Craftsa
    Opis:
    In order to fabricate graphite nanosheets from graphite flakes, edge-functionalized graphite nanosheets were prepared by a functionalization method using phthalic acid as the molecule to be grafted. A polyphosphoric acid/P2O5 solution containing graphite and phthalic acid were heated at different temperatures for 72 h in a nitrogen atmosphere. It was confirmed by transmission electron microscopy and atomic force microscopy that the resultant phthalic acid-functionalized graphite nanosheets had a large surface area of 20.69 μm2 in average and an average thickness of 1.39 nm. It was also found by X-ray diffractometry and Fourier transform infrared spectroscopy (FT-IR) analysis that the functionalization caused the formation of C=O bonds at the edges of the graphite nanosheets. The yield from this functionalization method was found to be dependent on the reaction temperature, only when it is between 70 and 130°C, because of the dehydration of phthalic acid at higher temperatures. This was confirmed by FT-IR analysis and the observation of low thermal energies at low temperatures.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1251-1255
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Molding Condition on Waviness Profile of GFRP Composites in Compression Molding
    Autorzy:
    Kim, J.
    Kim, H.
    Lee, D.
    Powiązania:
    https://bibliotekanauki.pl/articles/1399878.pdf
    Data publikacji:
    2013-02
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    81.05.Lg
    81.05.Qk
    88.30.mj
    Opis:
    During compression molding of glass fiber reinforced plastic composites, annealing and quenching experiment is conducted by changing pre-heating and cooling method. As results, major cause of unevenness that affects waviness profile (winding) is the shrinkage of matrix during holding and cooling process. Waviness profile of the surface on molding in glass fiber reinforced plastic composites will be lower when holding pressure load is higher, mold temperature is lower during demolding, and cooling rate is slower. In addition, surface roughness of moldings is depending on holding pressure load compared with mold temperature. According to molding condition of glass fiber reinforced plastic composites, waviness profile of surface can be quantitatively estimated using the proposed equation.
    Źródło:
    Acta Physica Polonica A; 2013, 123, 2; 337-340
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Extraction Factor Of Pure Ammonium Paratungstate From Tungsten Scraps
    Współczynnik ekstrakcji czystego parawolframianu amonu z odpadów wolframowych
    Autorzy:
    Pee, J-H.
    Kim, G. H.
    Lee, H. Y.
    Kim, Y. J.
    Powiązania:
    https://bibliotekanauki.pl/articles/356567.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    raw material
    recycling
    ammonium paratungstate
    tungsten scraps
    extraction
    surowce
    recykling
    parawolfrawian amonu
    odpady wolframowe
    ekstrakcja
    Opis:
    Typical oxidation process of tungsten scraps was modified by the rotary kiln with oxygen burner to increase the oxidation rate of tungsten scraps. Also to accelerate the solubility of solid oxidized products, the hydrothermal reflux method was adapted. By heating tungsten scraps in rotary kiln with oxygen burner at around 900° for 2hrs, the scraps was oxidized completely. Then oxidized products (WO3 and CoWO4) was fully dissolved in the solution of NaOH by hydrothermal reflux method at 150° for 2hrs. The dissolution rate of oxidized products was increased with increasing the reaction temperature and concentration of NaOH. And then CaWO4 and H2WO4 could be generated from the aqueous sodium tungstate solution. Ammonium paratungstate (APT) also could be produced from tungstic acid using by aqueous ammonium solution. The morphologies (cubic and plate types) of APT was controlled by the stirring process of purified solution of ammonium paratungstate.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1403-1405
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Study on detection of gross error in geodetic network adjustment
    Autorzy:
    Kim, J. H.
    Kim, C. J.
    Li, R. J.
    Powiązania:
    https://bibliotekanauki.pl/articles/145352.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    sieć geodezyjna
    sieć triangulacyjna
    geodezja satelitarna
    geodetic network adjustment
    gross error
    robust estimation
    equivalent weight
    Opis:
    Generally, gross errors exist in observations, and they affect the accuracy of results. We review methods to detect the gross errors by Robust estimation method based on L1-estimation theory and their validity in adjustment of geodetic networks with different condition. In order to detect the gross errors, we transform the weight of accidental model into equivalent one using not standardized residual but residual of observation, and apply this method to adjustment computation of triangulation network, traverse network, satellite geodetic network and so on. In triangulation network, we use a method of transforming into equivalent weight by residual and detect gross error in parameter adjustment without and with condition. The result from proposed method is compared with the one from using standardized residual as equivalent weight. In traverse network, we decide the weight by Helmert variance component estimation, and then detect gross errors and compare by the same way with triangulation network In satellite geodetic network in which observations are correlated, we detect gross errors transforming into equivalent correlation matrix by residual and variance inflation factor and the result is also compared with the result from using standardized residual. The results of detection are shown that it is more convenient and effective to detect gross errors by residual in geodetic network adjustment of various forms than detection by standardized residual.
    Źródło:
    Geodesy and Cartography; 2018, 67, 1; 57-69
    2080-6736
    2300-2581
    Pojawia się w:
    Geodesy and Cartography
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Extraction Factor Of Tungsten Sources From Tungsten Scraps By Zinc Decomposition Process
    Współczynnik ekstrakcji związków wolframu z odpadów wolframowych w procesie rozkładu cynku
    Autorzy:
    Pee, J-H.
    Kim, G. H.
    Lee, H. Y.
    Kim, Y. J.
    Powiązania:
    https://bibliotekanauki.pl/articles/354774.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    raw material
    recycling
    zinc decomposition process
    tungsten carbide
    tungstic acid
    surowce
    recykling
    proces rozkładu cynku
    węglik wolframu
    kwas wolframowy
    Opis:
    Decomposition promoting factors and extraction process of tungsten carbide and tungstic acid powders in the zinc decomposition process of tungsten scraps which are composed mostly of tungsten carbide and cobalt were evaluated. Zinc volatility was suppressed by the enclosed graphite crucible and zinc volatilization pressure was produced in the reaction graphite crucible inside an electric furnace for ZDP (Zinc Decomposition Process). Decomposition reaction was done for 2hours at 650°, which 100% decomposed the tungsten scraps that were over 30 mm thick. Decomposed scraps were pulverized under 75μm and were composed of tungsten carbide and cobalt identified by the XRD (X-ray Diffraction). To produce the WC(Tungsten Carbide) powder directly from decomposed scraps, pulverized powders were reacted with hydrochloric acid to remove the cobalt binder. Also to produce the tungstic acid, pulverized powders were reacted with aqua regia to remove the cobalt binder and oxidize the tungsten carbide. Tungsten carbide and tungstic acid powders were identified by XRD and chemical composition analysis.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1311-1314
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Formation of Different Cu Nanopowders and Stability of Cu Fluids Produced by Electrical Explosion of Wire in Liquid
    Autorzy:
    Nguyen, M.-T.
    Kim, J.-H.
    Kim, J.-C.
    Powiązania:
    https://bibliotekanauki.pl/articles/355217.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Cu nanopowder
    Cu nanofluids
    electrical explosion of wire
    stability of nanofluids
    Opis:
    In this study, copper nanoparticles and nanofluids were synthesized by electrical explosion of wire (EEW) in liquid media such as water, ethanol, and acetone. The effect of the different conditions on the properties of the as-synthesized Cu powders and nanofluids were investigated. X-ray diffraction (XRD) analysis was employed to measure the phase of the as-synthesized powder. Only pure Cu phase appeared in case of acetone condition, but CuO and CuO2 phases could be observed in the others. The EEWed particle size was broadened from under 50 to 100 nm. The results showed that acetone was the best condition for achieving smaller particles, preventing the oxidation of the Cu particles and good stability of the nanofluids.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 3; 1453-1457
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A Study on Discharge Characteristics by Using MF and RF Power in Remote Dielectric Barrier Discharge
    Autorzy:
    Kim, D.
    Shim, Y.
    Kim, H.
    Han, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1398758.pdf
    Data publikacji:
    2016-04
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    52.77.Bn
    Opis:
    We have developed an atmospheric pressure plasma apparatus of remote dielectric barrier discharge (RDBD) applicable for a large area. We have systematically studied the characteristics of medium frequency (MF, 40 kHz) and radio frequency (RF, 13.56 MHz) discharge using an optical emission spectroscope. Nitrogen (N₂) and argon (Ar) gases were used in the MF and RF discharge excitation, respectively, in a mixture with clean dry air (CDA). The peak of oxygen radical (O*₂) appears at 259.3 nm when the RDBD is employed. Furthermore, intensive peaks are observed at gas ratios of N₂:CDA=100:1 in MF excitation and at gas ratios of Ar:CDA=70:0.5 in RF discharge excitation. On the other hand, the contact angle shows about 5° in PET samples after the RDBD treatment using the RF and MF discharge excitation. Surface analyses of polyethylene terephthalate (PET) samples were carried out using an atomic force microscope and X-ray photoelectron spectroscope.
    Źródło:
    Acta Physica Polonica A; 2016, 129, 4; 707-710
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Sintering and Microstructures of SUS 316L Powder Produced by 3D Printing Process
    Autorzy:
    Kim, W. J.
    Nguyen, H.-H.
    Kim, H. Y.
    Nguyen, M.-T.
    Park, H. S.
    Kim, J.-C.
    Powiązania:
    https://bibliotekanauki.pl/articles/356018.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    stainless steel
    3D printing
    selective laser sintering
    SUS 316L
    flake powder
    Opis:
    Selective laser sintering (SLS) is a type of laminating sintering technique, using CO2 laser with (metal, polymer, and ceramic) powders. In this result, the flake SUS 316L was used to achieve a high porous product, and compare to spherical type. After SLS, the porosity of flake-type sample with 34% was quite higher than that of the spherical-type one that had only 11%. The surface roughness of the flake SLS sample were also investigated in both inner and surface parts. The results show that the deviation of the roughness of the surface part is about 64.40μm, while that of the internal one was about 117.65μm, which presents the containing of high porosity in the uneven surfaces. With the process using spherical powder, the sample was quite dense, however, some initial particles still remained as a result of less energy received at the beneath of the processing layer.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1215-1218
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    $SiO_x$ Nanowires Produced on Molybdenum-Coated Si Substrates
    Autorzy:
    Kim, H.
    Lee, J.
    Yang, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1813396.pdf
    Data publikacji:
    2008-03
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    81.07.-b
    78.55.-m
    Opis:
    We synthesized $SiO_x$ nanowires with diameters of 30-140 nm, for the first time by the simple heating of the Mo-coated Si substrates. X-ray diffraction, selected area electron diffraction, and energy-dispersive X-ray spectroscopy indicated that the nanowires were in an amorphous state, comprising Si and O only. Fitting the photoluminescence spectrum with Gaussian functions revealed that the nanowires exhibited significant photoluminescence intensities near blue and green light regions. We extensively discussed the possible growth mechanism of $SiO_x$ nanowires.
    Źródło:
    Acta Physica Polonica A; 2008, 113, 3; 1017-1020
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Heat Treatment on the Microstructure and Tensile Deformation Behavior of Oxide Dispersion Strengthened Alloys Manufactured by Complex Milling Process
    Autorzy:
    Kim, Y.-K.
    Kim, J.-H.
    Gwon, J.-H.
    Lee, K.-A.
    Powiązania:
    https://bibliotekanauki.pl/articles/352535.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    ball milling
    oxide dispersion strengthening
    microstructure
    tensile deformation behavior
    Opis:
    This study attempted to manufacture an ODS alloy by combining multiple milling processes in mechanical alloying stage to achieve high strength and fracture elongation. The complex milling process of this study conducted planetary ball milling, cryogenic ball milling and drum ball milling in sequential order, and then the microstructure and tensile deformation behavior were investigated after additional heat treatment. The oxide particles distributed within the microstructure were fine oxide particles of 5~20 nm and coarse oxide particles of 100~200 nm, and the oxide particles were confirmed to be composed of Cr, Ti, Y and O. Results of tensile tests at room temperature measured yield strength, tensile strength and elongation as 1320 MPa, 2245 MPa and 4.2%, respectively, before heat treatment, and 1161 MPa, 2020 MPa and 5.5% after heat treatment. This results indicate that the ODS alloy of this study gained very high strengths compared to other known ODS alloys, allowing greater plastic zones.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1335-1340
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Temperature Effect on the Growth Rate and Physical Characteristics of SnO2 Thin Films Grown by Atomic Layer Deposition
    Autorzy:
    Kim, D.
    Kim, D. H.
    Riu, D.-H.
    Choi, B. J.
    Powiązania:
    https://bibliotekanauki.pl/articles/353808.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    atomic layer deposition
    tin oxide
    growth rate
    film density
    optical band gap
    Opis:
    Among the various thin film coating techniques, atomic layer deposition (ALD) has features of good controllability of the thickness, excellent step-coverage in 3-dimensional object even in the sub-nm thickness range at the relatively low deposition temperature. In this study, SnO2 thin films were grown by ALD in the variation of substrate temperatures from 150 to 250°C. Even such a low temperature may influence on the growth kinetics of the ALD reaction and thus the physical characteristics of thin films, such as crystallinity, film density and optical band gap, etc. We observed the decrease of the growth rate with increasing substrate temperature, at the same time, the density of the film was decreased with increasing temperature. Steric hindrance effect of the precursor molecule was attributed to the inverse relationship of the growth temperature and growth rate as well as the film density. Optical indirect band gap energy (~3.6 eV) of the ALD-grown amorphous SnO2 films grown at 150°C was similar with that of the literature value, while slightly lower band gap energy (~3.4 eV) was acquired at the films grown at higher temperature.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 2; 1061-1064
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Hardness and Microstructure of Mixed Al-CNF Powder Extrusion
    Autorzy:
    Kim, D.-H.
    Kim, T.-J.
    Lim, S.-G.
    Powiązania:
    https://bibliotekanauki.pl/articles/351170.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Al-CNF composite
    cold isotatic
    presses
    powder extrusion
    LED
    microstructure
    Opis:
    In this study, mechanical properties and microstructures of extruded aluminum matrix composites were investigated. The composite materials were manufactured by two step methods: powder metallurgy (mixture of aluminum powder and carbon fiber using a turbular mixer, pressing of mixed aluminum powder and carbon fiber using a cold isostatic pressing) and hot extrusion of pressed aluminum powder and carbon fiber. For the mixing of Al powder and carbon fibers, aluminum powder was used as a powder with an average particle size of 30 micrometer and the addition of the carbon fibers was 50% of volume. In order to make mixing easier, it was mixed under an optimal condition of turbular mixer with a rotational speed of 60 rpm and time of 1800s. The process of the hot-extrusion was heated at 450°C for 1 hour. Then, it was hot-extruded with a condition of extrusion ratio of 19 and ram speed of 2 mm/s. The microstructural analysis of extruded aluminum matrix composites bars and semi-solid casted alloys were carried out with the optical microscope, scanning electron microscope and X-ray diffraction. Its mechanical properties were evaluated by Vickers hardness and tensile test.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1267-1270
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Development of Carbon Nanotube Based Reflection Type X-ray Source
    Autorzy:
    Choi, H.
    Kim, J.
    Lee, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1807922.pdf
    Data publikacji:
    2009-06
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    75.47.Lx
    75.47.Gk
    73.50.Fq
    Opis:
    X-ray imaging technology is a useful and leading medical diagnostic tool for health care professionals to diagnose disease in human body. Carbon nanotube based X-ray source, which we have developed in this study, could be also useful and supply integrated diagnostic X-ray imaging tool in diagnosis. Conventionally, thermionic type of tungsten filament X-ray tube is widely employed in the field of biomedical and industrial application fields. However, intrinsic problems, such as poor emission efficiency, low imaging resolution, and high electrical energy consumption etc., may cause the limitation of using the X-ray tube. To fulfill the current market requirement, specifically for medical diagnostic field, we have developed rather a portable and compact carbon nanotube based X-ray device in which microfocus high imaging resolution can be feasible.
    Źródło:
    Acta Physica Polonica A; 2009, 115, 6; 1078-1080
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect Of Carbon Nanotubes On The Properties Of Spark Plasma Sintered ZrO2/CNT Composites
    Wpływ nanorurek węglowych na właściwości spiekanych metodą sps kompozytów ZrO2/CNT
    Autorzy:
    Shim, D. H.
    Jung, S. S.
    Kim, H. S.
    Cho, H.
    Kim, J. K.
    Kim, T. G.
    Yoon, S. J.
    Powiązania:
    https://bibliotekanauki.pl/articles/351266.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    CNT
    ZrO2
    composite
    SPS
    kompozyty
    Opis:
    Zirconia matrix ZrO2/CNT composite materials reinforced with multiwall carbon nanotubes were fabricated using a spark plasma sintering technique. The effects of the amount of CNTs addition, sintering temperature and sintering pressure on the properties of the resulting ZrO2/CNT composites were examined. 0 to 9 vol. % CNTs were dispersed in zirconia powder, and the resulting mixture was sintered. The electrical conductivity, hardness, flexural strength, and density were measured to characterize the composites. The friction and wear properties of the composites were also tested. The flexural strength and friction coefficient of the composites were improved with up to 6 vol.% of CNT addition and the flexural strength showed a close relationship with the relative density of the composite. The electrical conductivity increased with increasing proportion of the CNTs, but the efficiency was reduced at more than 6 vol.% CNTs.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1315-1318
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Preparation of Nickel Powders by Reduction of Nickel Hydroxide Using the Taylor Fluid Flow
    Autorzy:
    Park, I.-J.
    Kim, D.-W.
    Kim, G.-H.
    Chae, H.-J.
    Jung, H.-C.
    Powiązania:
    https://bibliotekanauki.pl/articles/355021.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Ni(OH)2
    nickel
    Taylor fluid flow
    fine powder
    Opis:
    In this study, Ni(OH)2 was synthesized by the continuous reaction by the Taylor fluid flow and compared with those prepared from the conventional batch type reaction. The nickel powders were synthesized by reduction of Ni(OH)2 in an aqueous solution with hydrazine hydrate acting as the reductant. And then the characteristics of the nickel powder according to the synthesis method were compared. The average particle size of the synthesized Ni(OH)2 using Taylor reactor was generally decreased about 1.5~2.5 times more than the batch reaction. The nickel powders prepared by the batch reaction highly agglomerated with non-uniform particles. In the Taylor reaction, the agglomeration of particles was broken and uniform nickel powder was produced.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 3; 1443-1447
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Boundary element modelling of wave diffraction by interaction with wave-offshore structure and dredged region
    Autorzy:
    Kim, S. D.
    Lee, H. J.
    Powiązania:
    https://bibliotekanauki.pl/articles/259525.pdf
    Data publikacji:
    2010
    Wydawca:
    Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
    Tematy:
    Submarine pit
    Green function
    boundary integral approach
    breakwater
    Opis:
    The purpose of this study is to estimate the wave height at the front face of breakwater (Refracted breakwater and Straight breakwater), when dredging like the submarine pit is performed in the distant offshore from outer breakwater. The wave field of the problem is considered to be two dimensional planes and the configuration of the pit region is designated by a single horizontal long-rectangular system. The numerical approach uses the Green function based on the boundary integral approach. The results of the present numerical works are illustrated by applying the normal and inclined incidence. It is shown that in the case of normal incidence, the ratio of wave height reduction at the front face of both types of breakwaters is approximately more than 20% due to the effect of the submarine pit on the sea bed. Furthermore, regardless of the type of breakwater and the difference in incident wave angles, the ratio of wave height was shown to be reduced.
    Źródło:
    Polish Maritime Research; 2010, 2; 67-71
    1233-2585
    Pojawia się w:
    Polish Maritime Research
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Catalyst-Free Growth of Magnesium Oxide Whiskers and Their Characteristics
    Autorzy:
    Kim, H.
    Kong, M.
    Yang, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1813397.pdf
    Data publikacji:
    2008-03
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    81.07.-b
    78.55.-m
    Opis:
    This study reports the production of magnesium oxide (MgO) whiskers on silicon (Si) substrates by the thermal heating of $MgB_2$ powders. We investigated the structural properties of the as-synthesized whiskers by using X-ray diffraction, transmission electron microscopy, selected area electron diffraction, and scanning electron microscopy. The product consisted of one-dimensional whiskers with a square cross-section. The whiskers had a single-crystalline cubic structure of MgO. The photoluminescence measurement with the Gaussian fitting exhibited visible light emission bands centered at 2.39 eV and 2.91 eV. We proposed the growth of MgO whiskers to follow the vapor-solid mechanism.
    Źródło:
    Acta Physica Polonica A; 2008, 113, 3; 1021-1024
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Study on Effects of Mold Temperature on the Injection Molded Article
    Autorzy:
    Han, J.-H.
    Kim, Y.-C.
    Powiązania:
    https://bibliotekanauki.pl/articles/351919.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    injection molding
    mold temperature
    cooling temperature
    molded article
    Opis:
    This is a study of the effects of temperature of injection mold on the injection molded article. By supplying water of the proper temperature in the cooling line of mold in the cooling process, the mold was the appropriate temperature, and the deformation of the injection molded article was examined according to the mold temperature. In this study, we conducted simulation analysis and experiments, and the results were analyzed. The minimum deformation of the injection molded article model obtained by supplying 50°C water in the cooling line is 0.003 mm, and the maximum deformation was 0.813 mm. Injection molded article models obtained by supplying 20°C water were found to be a minimum of 0.002 mm, with deformation of up to 0.761 mm. When comparing both conditions, the error rate of injection molded article obtained by supplying 20°C water in the mold cooling line was lower by about 0.18%.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1271-1274
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Influence of InAs Coverage on Transition of Size Distribution and Optical Properties of InAs Quantum Dots
    Autorzy:
    Kim, G.
    Jeon, S.
    Cho, M.
    Choi, H.
    Kim, D.
    Kim, M.
    Kwon, Y.
    Choe, J.
    Kim, J.
    Leem, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1535820.pdf
    Data publikacji:
    2010-10
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    81.15.Hi
    68.37.Ps
    78.55.Cr
    78.67.Hc
    Opis:
    The influence of InAs coverage on the formation of self-assembled quantum dots grown by molecular-beam epitaxy was investigated by atomic force microscopy and photoluminescence measurements. As the InAs coverage increased from 2.0 to 3.0 monolayers, the quantum dot density decreased from 1.1 × $10^{11}$ to 1.36 × $10^{10} cm^{-2}$. This result could be attributed to the coalescence of neighboring small InAs quantum dots resulting in the formation of much larger InAs quantum dots with lower quantum dot density. Atomic force microscopy results revealed that as the InAs quantum dot coverage increased, the transition of size distribution of InAs quantum dots from single-modal to multimodal occurred. The temperature-dependent photoluminescence spectra showed that the photoluminescence spectra red shifted and the photoluminescence peak intensity decreased as the InAs coverage increased. The thermal activation energy was strongly dependent on the InAs coverage, and for InAs quantum dots with 3.0 ML thick InAs coverage, this energy was estimated to be 147 meV.
    Źródło:
    Acta Physica Polonica A; 2010, 118, 4; 673-676
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Synthesis, Structure, Photoluminescence, and Raman Spectrum of Indium Oxide Nanowires
    Autorzy:
    Kim, H.
    Na, H.
    Yang, J.
    Lee,, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1505485.pdf
    Data publikacji:
    2011-02
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    81.07.-b
    78.55.-m
    Opis:
    Production of indium oxide $(In_2O_3)$ whiskers at a very low temperature of 650°C was reported. The synthetic route was comprised of a thermal heating process of a mixture of In and Mg powders. We have investigated the structural properties of the as-synthesized nanowires by using X-ray diffraction and scanning electron microscopy. The product consisted of one-dimensional nanowires, with a crystalline cubic structure of $In_2O_3$. The photoluminescence measurement with the Gaussian fitting exhibited visible light emission bands centered at 2.1 eV and 2.8 eV. The peaks of the Raman spectrum were indexed to the modes being associated with cubic $In_2O_3$.
    Źródło:
    Acta Physica Polonica A; 2011, 119, 2; 143-145
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Effect of Additive Element on the Properties of Mechanically Alloyed Fe-Y2O3 Alloys
    Autorzy:
    Ahn, J.-H.
    Kim, T. K.
    Ahn, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/356561.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    mechanical alloying
    ODS alloy
    nanoparticles
    oxide dispersion strengthening
    high-energy ball milling
    Opis:
    In the present work, we have examined the effect of Ti on the properties of Fe-Y2O3 alloys. The result showed that the addition of Ti was effective for improving mechanical properties. This is due to the reduction of oxides by Ti during mechanical alloying and hot-consolidation. In particular, iron oxides are effectively reduced by the addition of Ti. Compared to the pristine Fe-Y2O3 alloys, titanium-added alloys exhibited fine and uniform microstructures, resulting in at least 60% higher tensile strength.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1043-1046
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication of Mo-Si-B Intermetallic Compound Powders Under Different Heat Treatment Conditions
    Autorzy:
    Park, J. H.
    Lee, S.
    Kim, D.
    Kim, Y.
    Yang, S. H.
    Lee, S. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/353369.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Mo-Si-B alloys
    intermetallic compounds
    reitveld refinement
    T2 phase
    A15 phase
    Opis:
    In this research, we investigated the effects of reduction atmospheres on the creation of the Mo-Si-B intermetallic compounds (IMC) during the heat treatments. For outstanding anti-oxidation and elevated mechanical strength at the ultrahigh temperature, we fabricated the uniformly dispersed IMC powders such as Mo5SiB2 (T2) and Mo3Si (A15) phases using the two steps of chemical reactions. Especially, in the second procedure, we studied the influence of the atmospheres (e.g. vacuum, argon, and hydrogen) on the synthesis of IMCs during the reduction. Furthermore, the newly produced IMCs were observed by SEM, XRD, and EDS to identify the phase of the compounds. We also calculated an amount of IMCs in the reduced powders depending on the atmosphere using the Reitveld refinement method. Consequently, it is found that hydrogen atmosphere was suitable for fabrication of IMC without other IMC phases.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 3; 1509-1512
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication and Characterization of GaN/Polymer Composite p-n Junction with PEDOT Nanoparticle Interface Layer
    Autorzy:
    Kim, M.
    Jin, S.
    Choi, H.
    Kim, G.
    Yim, K.
    Kim, S.
    Nam, G.
    Yoon, H.
    Kim, Y.
    Lee, D.
    Kim, Jin
    Kim, Jong
    Leem, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1505152.pdf
    Data publikacji:
    2011-06
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    73.61.Ey
    81.15.Gh
    Opis:
    A heavily Si-doped GaN/polymer hybrid structure with p-type poly(3,4-ethylene-dioxythiophene):beta-1,3-glucan (PEDOT nanoparticle) interface layer has been fabricated. The Si-doped GaN thin film with carrier concentration of 1 × $10^{19} cm^{-3}$ was grown by metal-organic chemical vapor deposition. The PEDOT nanoparticle with various sizes ranging from 60 to 120 nm was synthesized via a miniemulsion polymerization process. The electrical conductivity of the PEDOT nanoparticle is less than 1.2 S/cm. The current-voltage (I-V) characteristic of the hybrid structure shows diode-like behavior. The I-V characteristic was examined in the framework of the thermionic emission model. The ideality factor of the structure without PEDOT nanoparticle interface layer is 12.9. However, the ideality factor of the hybrid structure with PEDOT nanoparticle interface layer is obtained as 1.9. The value of ideality factor is dramatically decreased by inserting the PEDOT nanoparticle interface layer.
    Źródło:
    Acta Physica Polonica A; 2011, 119, 6; 875-879
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Optical Properties of Multi-Stacked InAs Quantum Dots Embedded in GaAs/InGaAs Strained Layer and its Annealing Behaviors
    Autorzy:
    Kim, D.
    Kim, G.
    Jeon, S.
    Cho, M.
    Choi, H.
    Kim, M.
    Lee, D.
    Kim, J.
    Eom, G.
    Leem, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1537752.pdf
    Data publikacji:
    2010-06
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    78.67.Hc
    78.55.Cr
    81.05.Ea
    Opis:
    Multi-stacked InAs QDs embedded in ten periods of GaAs/$In_{0.1}Ga_{0.9}As$ strained layers were grown by MBE and their optical properties were investigated by using PL spectroscopy. For the QDs embedded in ten periods of GaAs/$In_{0.1}Ga_{0.9}As$ strained layers, the PL intensity is enhanced about 4.7 times and a narrower FWHM of 26 meV is observed compared to those of the conventional multi-stacked QDs. The PL spectra of the InAs QDs show blue-shifts of about 50 meV with increasing annealing temperature up to 850°C. At annealing temperature of 600°C, the FWHM of the PL peak is reduced to 16 meV and PL intensity is enhanced compared to those of the as-grown sample, which indicates improvement of size uniformity and crystal quality of the QDs.
    Źródło:
    Acta Physica Polonica A; 2010, 117, 6; 941-944
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Application of Image Processing to Predict Compressive Behavior of Aluminum Foam
    Autorzy:
    Kim, S.
    Chung, H. J.
    Rhee, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/357032.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    aluminum foam
    compute tomography (CT) image
    finite element method (FEM)
    Opis:
    An image processing technique was used to model the internal structure of aluminum foam in finite element analysis in order to predict the compressive behavior of the material. Finite element analysis and experimental tests were performed on aluminum foam with densities of 0.2, 0.25, and 0.3 g/cm3. It was found that although the compressive strength predicted from the finite element analysis was higher than that determined experimentally, the predicted compressive stress-strain curves exhibited a tendency similar to those determined from experiments for both densities. However, the behavior of the predicted compressive stress-strain curves was different from the experimental one as the applied strain increased. The difference between predicted and experimental stress-strain curves in a high strain range was due to contact between broken aluminum foam walls by the large deformation.
    Źródło:
    Archives of Metallurgy and Materials; 2016, 61, 2A; 635-640
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Design Of A Bi-Functional α-Fe2O3/Zn2SiO4:Mn2+ By Layer-By-Layer Assembly Method
    Projektowanie dwufunkcyjnych proszków α-Fe2O3/Zn2SiO4:Mn2+ metodą warstwa po warstwie
    Autorzy:
    Yu, R.
    Yun, J.
    Pee, J-H.
    Kim, Y.
    Powiązania:
    https://bibliotekanauki.pl/articles/352623.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    red pigment
    α-Fe2O3
    Zn2SiO4:Mn2+ layer
    phosphor
    bi-functional
    czerwony pigment
    Zn2SiO4: Mn2+
    fosfor
    proszki dwufunkcyjne
    Opis:
    This work describes the design of bi-functional α-Fe2O3/Zn2SiO4:Mn2+ using a two-step coating process. We propose a combination of pigments (α-Fe2O3) and phosphor (Zn2SiO4:Mn2+ ) glaze which is assembled using a layer-by-layer method. A silica-coated α-Fe2O3 pigment was obtained by a sol-gel method and a Zn2+ precursor was then added to the silica-coated α-Fe2O3 to create a ZnO layer. Finally, the Zn2SiO4:Mn2+ layer was prepared with the addition of Mn2+ ions to serve as a phosphor precursor in the multi-coated α-Fe2O3, followed by annealing at a temperature above 1000°C. Details of the phase structure, color and optical properties of the multi-functional α-Fe2O3/Zn2SiO4:Mn2+ were characterized by transmission electron microscopy and X-ray diffraction analyses.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1165-1167
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Study On The Electro-Refining Of Tin In Acid Solution From Electronic Waste
    Badanie elektrorafinacji cyny w roztworze kwasu z e-odpadów
    Autorzy:
    Son, S. H.
    Park, S. C.
    Kim, J. H.
    Kim, Y. H.
    Lee, M. S.
    Ahn, J.-W.
    Powiązania:
    https://bibliotekanauki.pl/articles/352665.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    electrorefining
    tin
    electronic waste
    recycling
    high purity
    elektrorafinacja
    cyna
    odpady elektroniczne
    recykling
    Opis:
    The tin metal could be retractable from wasted tin scrap, sludge, and wasted electroplated solution hydrometallurgical treatment, and purification process. In order to be used as resource of electronic devices, the retracted crude metal should be purified to the extent of higher than 99.9%. In this study, tin electro-refining process was performed to purify the casted tin crude metal at various experimental conditions: at the current density of 3, 5A/dm2, and in various electrolytes such as hydrochloric acid, sulfuric acid and methansulfonic acid. Additional experiment was conducted using Rotating Disk Electrode (RDE) in order to investigate the rate determining step of tin electro-refining process. The current efficiency, 65.6%, was achievable at the condition of current density, 5A/dm2, and in the electrolyte of Hydrochloric acid. During tin electro-refining process, impurity dissolved from tin crude metal into the electrolyte was analyzed using Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES), and the result showed the concentration of impurity metal gradually increased. Quantitative analysis on casted tin crude metal showed that it consists of tin with 93.9 wt.% and several impurity metals of Ag, Bi, Pb, Cu, and etc. After tin electro-refining process, the purity of tin increased up to 99.985 wt.%.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1217-1220
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A Systematic Procedure for Modeling Usability Based on Product Design Variables: A Case Study in Audiovisual Consumer Electronic Products
    Autorzy:
    Kim, K.-J.
    Han, S. H.
    Yun, M. H.
    Kwahk, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/90811.pdf
    Data publikacji:
    2002
    Wydawca:
    Centralny Instytut Ochrony Pracy
    Tematy:
    usability evaluation
    human interface elements
    consumer electronic products
    produkty przemysłowe
    ocena zgodności wyrobów
    ocena użyteczności
    produkty elektroniczne
    Opis:
    A systematic modeling approach to describing, prescribing, and predicting usability of a product has been presented. Given the evaluation results of the usability dimension (UD) and the measurement of the product’s design variables, referred to as the human interface elements (HIEs), the approach enables one to systematically assess the relationship between the UD and HIEs. The assessed relationship is called a usability model. Once built, such a usability model can relate, in a quantitative manner, the HIEs directly to the UDs, and thus can serve as an effective aid to designers by evaluating and predicting the usability of an existing or hypothetical product. A usability model for elegance of audiovisual consumer electronic products has been demonstrated.
    Źródło:
    International Journal of Occupational Safety and Ergonomics; 2002, 8, 3; 387-406
    1080-3548
    Pojawia się w:
    International Journal of Occupational Safety and Ergonomics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Formation of Tungsten/Ammonium Perchlorate Composites and Their Reaction Kinetics
    Autorzy:
    Shim, H.-M.
    Lee, E.-A.
    Kim, J.-K.
    Kim, H.-S.
    Koo, K.-K.
    Powiązania:
    https://bibliotekanauki.pl/articles/358373.pdf
    Data publikacji:
    2015
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
    Tematy:
    ammonium perchlorate
    composite
    thermal decomposition
    Opis:
    The reaction kinetics of tungsten nanoparticles/ammonium perchlorate (W/AP) composites, produced by a spray drying technique, were analyzed and compared with those of neat AP particles and aluminum nanoparticles/AP (Al/AP) composites. The W was found to raise the onset temperature of the thermal decomposition of AP by increasing the activation energy, whereas Al conversely lowered the onset temperature of AP due to the decreased activation energy. From the master plots of kinetic models with the experimental data, the Prout-Tompkins model and the 1-D diffusion controlled model were found to describe the low-temperature decomposition (LTD) and high-temperature decomposition (HTD), respectively, giving remarkable agreement with experimental curves for all heating rates. The presence of W was found to increase the HTD zone width compared with that of neat AP particles and Al/AP composites. Analysis of the average activation energy and pre-exponential factor showed that W increases the energy barrier and the frequency of occurrence of the reaction compared with that of neat AP particles at the LTD state, whereas W decreases both of them at the HTD state. The effect of Al was also shown to be similar to that of W, but the magnitudes of the variation in activation energy and the pre-exponential factor were relatively small.
    Źródło:
    Central European Journal of Energetic Materials; 2015, 12, 4; 703-722
    1733-7178
    Pojawia się w:
    Central European Journal of Energetic Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Hafnium and Zirconium to Glass Forming Ability, Thermal Stability, Plasticity Deformation and Crystallization of Ni-Free Pentabasic Ti-Based Bulk Metallic Glasses
    Autorzy:
    Oak, J.-J.
    Kim, Y. H.
    Bae, K.-C.
    Park, Y. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/352087.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Ti-based alloy
    metallic glass
    Ti fiber
    glass formability
    plastic deformation
    Opis:
    The newly designed Ti-based bulk metallic glass (BMG) in which case of fracture behavior was observed 1990MPa to compressive strength with a wide plastic deformation around 7% after process of elastic deformation. This phenomenon can be compared with those of Ti-based alloys and other Ti-based BMGs and indicates high potential to be applied in use. It was evaluated the Ti-based BMG for thermal stability that the reduced glass parameters, ΔTx, Trg and γ, are 79K, 0.50 and 0.38, respectively. In addition, it reveals high activation energies for crystallization in which are estimated to Ex1 = 291.77 ±9.71 kJ/mol, Ex2 = 588.77 ±28.88 kJ/mol and Ex3 = 330.26 ±3.61 kJ/mol on kissinger plotting in this study.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1081-1087
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Microstructure And Thermoelectric Properties Of TAGS-90 Compounds Fabricated By Mechanical Milling Process
    Mikrostruktura i właściwości termoelektryczne związków TAGS-90 wytworzonych przez mielenie
    Autorzy:
    Kim, H.-S.
    Babu, M.
    Hong, S.-J.
    Powiązania:
    https://bibliotekanauki.pl/articles/353404.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    TAGS-90
    thermoelectric properties
    high-energy milling
    SPS
    właściwości termoelektryczne
    mielenie wysokoenergetyczne
    Opis:
    TAGS-90 compound powder was directly prepared from the elements by high-energy ball milling (HEBM) and subsequently consolidated by a spark plasma sintering (SPS). Effect of milling time on the microstructure and thermoelectric properties of the samples were investigated. The particle size of fabricated powders were decreased with increasing milling time, finally fine particles with ~1μm size was obtained at 90 min. The SPS samples exhibited higher relative densities (>99%) with fine grain size. X-ray diffraction analysis (XRD) and energy dispersion analysis (EDS) results revealed that all the samples were single phase of GeTe with exact composition. The electrical conductivity of samples were decreased with milling time, whereas Seebeck coefficient increased over the temperature range of RT~450°C. The highest power factor was 1.12×10-3 W/mK2 obtained for the sample with 90 min milling at 450°C.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1231-1234
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effects of Grain Boundary Morphologies on Stress Corrosion Cracking of Alloy 600
    Autorzy:
    Kim, H. P.
    Choi, M. J.
    Kim, S. W.
    Kim, D. J.
    Lim, Y. S.
    Hwang, S. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/352569.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    alloy 600
    NaOH
    stress corrosion cracking
    grain boundary morphologies
    Opis:
    Effects of grain boundary morphologies on stress corrosion cracking (SCC) of Alloy 600 have been studied in 40% NaOH at 315°C using C-ring specimens. The configuration of the grain boundary and the intergranular carbide density were controlled by heat treatment. SCC tests were performed at +150 mV above the corrosion potential. The specimen with a serrated grain boundary showed higher SCC resistance than that with a straight grain boundary. This appears to be caused by the fact that the specimen with the serrated grain boundary has longer SCC path. SCC resistance also increased with intergranular carbide density probably due to enhanced relaxation of stress at intergranular carbide.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1415-1419
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect Of Different Mechanical Milling Processes On Morphology And Microstructural Changes Of Nano And Micron Al-Powders
    Wpływ różnych procesów mielenia na morfologię i mikrostrukturę nanometrycznych i mikronowych proszków Al
    Autorzy:
    Kim, H.-S.
    Madavali, B.
    Eom, T.-J.
    Kim, C.- M.
    Koo, J.-M.
    Lee, T. H.
    Hong, S.-J.
    Powiązania:
    https://bibliotekanauki.pl/articles/355715.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Al alloys
    high-energy ball milling
    low energy ball milling
    plastic deformation
    stopy Al
    wysokoenergetyczne mielenie kulkowe
    mielenie energooszczędne
    odkształcenia plastyczne
    Opis:
    In this research, effect of the various mechanical milling process on morphology and microstructural changes of nano and micron Al-powders was studied. The milling of Al-powders was performed by both high energy and low energy ball milling process. The influence of milling (pulverizing) energy on the structural changes of Al-powders was studied. Al-nanoparticles were agglomerated during the MA and its size was increased with increasing milling while micron Al-powder gets flattened shape during high energy ball milling due to severe plastic deformation. Meanwhile, structural evolution during high energy ball milling of the nano powder occurred faster than that of the micron powder. A slight shift in the position of X-ray diffraction peaks was observed in nano Al-powders but it was un-altered in macro Al-powders. The variation in lattice parameters was observed only for nano Al powders during the high energy ball milling due to lattice distortion.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1235-1239
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Heat Treatment on Microstructure and Impact Toughness of Ti-6Al-4V Manufactured by Selective Laser Melting Process
    Autorzy:
    Lee, K.-A.
    Kim, Y.-K.
    Yu, J.-H.
    Park, S.-H.
    Kim, M.-C.
    Powiązania:
    https://bibliotekanauki.pl/articles/354570.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    selective laser melting
    Ti-6Al-4V
    microstructure
    impact toughness
    heat treatment
    Opis:
    This study manufactured Ti-6Al-4V alloy using one of the powder bed fusion 3D-printing processes, selective laser melting, and investigated the effect of heat treatment (650°C/3hrs) on microstructure and impact toughness of the material. Initial microstructural observation identified prior-β grain along the building direction before and after heat treatment. In addition, the material formed a fully martensite structure before heat treatment, and after heat treatment, α and β phase were formed simultaneously. Charpy impact tests were conducted. The average impact energy measured as 6.0 J before heat treatment, and after heat treatment, the average impact energy increased by approximately 20% to 7.3 J. Fracture surface observation after the impact test showed that both alloys had brittle characteristics on macro levels, but showed ductile fracture characteristics and dimples at micro levels.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1341-1346
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Fe Content on the Microstructure and Mechanical Properties of Ti-Al-Mo-V-Cr-Fe Alloys
    Autorzy:
    Bae, K.-C.
    Oak, J.-J.
    Kim, Y. H.
    Park, Y. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/351896.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Ti alloy
    near-β titanium alloy
    aircraft applications
    structural material
    landing gear
    Opis:
    To investigate the effect of Fe content on the correlation between the microstructure and mechanical properties in near-b titanium alloys, the Ti-5Al-5Mo-5V-1Cr-xFe alloy system has been characterized in this study. As the Fe content increased, the number of nucleation sites and the volume fraction of the α phase decreased. We observed a significant difference in the shape and size of the α phase in the matrix before and after Fe addition. In addition, these morphological deformations were accompanied by a change in the shape of the α phase, which became increasingly discontinuous, and changed into globular-type α phase in the matrix. These phenomena affected the microstructure and mechanical properties of Ti alloys. Specimen #2 exhibited a high ultimate tensile strength (1071 MPa), which decreased with further addition of Fe.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1105-1108
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Compressive Deformation Behavior of Thick Micro-Alloyed HSLA Steel Plates at Elevated Temperatures
    Autorzy:
    Lee, J.-H.
    Kim, D.-O.
    Lee, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/351774.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    alloys
    rolling
    strain rate
    compression test
    HSLA steel
    Opis:
    The hot deformation behavior of a heavy micro-alloyed high-strength low-alloy (HSLA) steel plate was studied by performing compression tests at elevated temperatures. The hot compression tests were carried out at temperatures from 923 K to 1,223 K with strain rates of 0.002 s-1 and 1.0 s-1. A long plateau region appeared for the 0.002 s-1 strain rate, and this was found to be an effect of the balancing between softening and hardening during deformation. For the 1.0 s-1 strain rate, the flow stress gradually increased after the yield point. The temperature and the strain rate-dependent parameters, such as the strain hardening coefficient (n), strength constant (K), and activation energy (Q), obtained from the flow stress curves were applied to the power law of plastic deformation. The constitutive model for flow stress can be expressed as σ = (39.8 ln (Z) – 716.6) · ε(−0.00955ln(Z) + 0.4930) for the 1.0 s-1 strain rate and σ = (19.9ln (Z) – 592.3) · ε(−0.00212ln(Z) + 0.1540) for the 0.002 s-1 strain rate.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1191-1196
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Spontaneous Formation of Titanium Nitride on the Surface of a Ti Rod Induced by Electro-Discharge-Heat-Treatment in an N2 Atmosphere
    Autorzy:
    Lee, W. H.
    Yoon, Y. H.
    Kim, Y. H.
    Lee, Y. K.
    Kim, J. Y.
    Chang, S. Y.
    Powiązania:
    https://bibliotekanauki.pl/articles/352477.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    titanium
    surface modification
    diffusion
    heat treatment
    XPS
    Opis:
    A single pulse of 2.0 to 3.5 kJ of input energy from a 450 mF capacitor was applied to a commercially pure Ti rod in a N2 atmosphere. The surface of the Ti rod transformed from TiO2 into titanium nitride in times as short as 159 msec, providing a bimodal morphology of the cross-section. A much higher value of hardness that was observed at the edge of the cross-section was attributed to nitrogen-induced solid-solution hardening that occurred during the electrical discharge process. The activation energy (Ea) for the diffusion process was estimated to be approximately 86.9 kJ/mol. Results show that the electrical discharge process is a possible potential method for the nitriding of Ti; advantages include a short processing time and control of the nitrided layer without dimensional changes.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1281-1285
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effects of acute lipopolysaccharide-induced toxemia model on some neglected blood parameters
    Autorzy:
    Adam, G.O.
    Lee, H.R.
    Lee, S.J.
    Kim, S.J.
    Kim, G.B.
    Kang, H.S.
    Powiązania:
    https://bibliotekanauki.pl/articles/2087627.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Toxemia
    lipopolysaccharide
    base excess
    pH
    animal model
    Źródło:
    Polish Journal of Veterinary Sciences; 2018, 21, 4; 665-671
    1505-1773
    Pojawia się w:
    Polish Journal of Veterinary Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Oxidation Behavior of Steel with Cr Content and Water Flow Rate
    Autorzy:
    Kim, D.-J.
    Kim, K. M.
    Shin, J. H.
    Cheong, Y. M.
    Lee, E. H.
    Lee, G. G.
    Kim, S. W.
    Kim, H. P.
    Choi, M. J.
    Lim, Y. S.
    Hwang, S. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/351548.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    steel
    flow accelerated corrosion
    Cr content
    flow rate
    surface oxides
    Opis:
    Fast water flow facilitates ferrous ion transport leading to flow accelerated corrosion (FAC) of carbon steel and the possibility of a large accident through a failure of a secondary pipe in a nuclear power plant. Ion transport is directly linked to oxide properties such as the thickness, chemical composition and porosity. This work deals with a precise observation of the cross section of the corroded specimen focusing on an oxide passivity and its thickness using SEM (scanning electron microscope) and TEM (transmission electron microscope) as well as an apparent weight loss and a surface observation for the specimens corroded using a rotating cylindrical electrode autoclave system in pure water of pH 7 at 150°C having dissolved oxygen below 1 ppb within a flow rate range of 0 to 10 m/s. The Cr content in steel was changed from 0.02 to 2.4 wt%. Increasing the Cr content in the alloy, the FAC rate and oxide thickness decreased. The oxide porosity tends to decrease with the Cr content and immersion time owing to the development of Cr containing oxide. The oxidation behavior is not changed with the immersion time.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1383-1387
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Acid Dissolution Conditions on Recovery of Valuable Metals from Used Plasma Display Panel Scrap
    Autorzy:
    Kim, C.- M.
    Dharmaiah, P.
    Kim, H.-S.
    Koo, J.-M.
    Yoon, J.-S.
    Hong, S.-H.
    Hong, S.-J.
    Powiązania:
    https://bibliotekanauki.pl/articles/355713.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    high energy ball milling
    waste plasma display panels
    dissolution
    recovery
    Opis:
    The objective of this particular study was to recover valuable metals from waste plasma display panels using high energy ball milling with subsequent acid dissolution. Dissolution of milled (PDP) powder was studied in HCl, HNO3, and H2SO4 acidic solutions. The effects of dissolution acid, temperature, time, and PDP scrap powder to acid ratio on the leaching process were investigated and the most favorable conditions were found: (1) valuable metals (In, Ag, Mg) were recovered from PDP powder in a mixture of concentrated hydrochloric acid (HCl:H2O = 50:50); (2) the optimal dissolution temperature and time for the valuable metals were found to be 60°C and 30 min, respectively; (3) the ideal PDP scrap powder to acid solution ratio was found to be 1:10. The proposed method was applied to the recovery of magnesium, silver, and indium with satisfactory results.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1173-1177
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An analysis on the thermal characteristics according to the viscosity of bearing lubricant and the cooling condition for the high speed motor spindle
    Autorzy:
    Choi, D. B.
    Lee, J. J.
    Kim, S. T.
    Kwon, H. D.
    Kim, C. Y.
    Powiązania:
    https://bibliotekanauki.pl/articles/1429194.pdf
    Data publikacji:
    2008
    Wydawca:
    Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
    Tematy:
    high speed motor spindle
    thermal displacement cooling condition
    lubricant viscosity
    Opis:
    Thermal displacement of the high speed machine tools has a large influence on machining accuracy. The high speed motor spindle with many heat sources is widely used for the high speed machine tools recently. The important problem in this spindle is to reduce and minimize the thermal effects by motor and bearings. This paper presents the analysis on thermal characteristics for high speed motor spindle system with oil-air lubricated angular contact ceramic ball bearings and built-in motor. An analysis on the thermal characteristics of spindle is performed according to the cooling conditions and the viscosity of bearing lubricants by using finite element method. This results can be applied to the design and manufacturing for the high speed motor spindle.
    Źródło:
    Journal of Machine Engineering; 2008, 8, 4; 88-98
    1895-7595
    2391-8071
    Pojawia się w:
    Journal of Machine Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    High-temperature Oxidation Behavior and Kinetics of Forged 12Cr-MoVW Steel
    Autorzy:
    Kim, Y. H.
    Oak, J.-J.
    Bae, K.-C.
    Lee, W-J.
    Park, Y. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/351450.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    ferritic/martensitic stainless steels
    forging
    oxidation kinetics
    oxide layer
    Opis:
    The oxidation kinetics of forged 12Cr-MoVW steel was investigated in an air (N2+O2) atmosphere at 873-1073 K (Δ50 K) using thermogravimetric analysis. The oxidized samples were characterized using X-ray diffraction, and the surface and cross-sectional morphologies were examined using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. The forged 12Cr-MoVW steel samples exhibited parabolic behavior and a low oxidation rate compared with their as-cast counterparts. A protective oxide layer was uniformly formed at relatively low temperature (≤973 K) for the forged samples, which thus exhibited better oxidation resistance than the as-cast ones. These oxides are considered solid-solution compounds such as (Fe, Cr)2O3.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1099-1104
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Warm Tensile Deformation Behavior and Constitutive Equation of Supersaturated Solid-Solutionized Al-9Mg Extruded Alloy
    Autorzy:
    Yang, Seung Y.
    Kim, Bong H.
    Lee, Da B.
    Choi, Kweon H.
    Kim, Nam S.
    Ha, Seong H.
    Yoon, Young O.
    Lim, Hyun K.
    Kim, Shae
    Kim, Young J.
    Powiązania:
    https://bibliotekanauki.pl/articles/2048882.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    aluminum alloy
    Al-9Mg alloy
    tensile test
    constitutive equation
    Opis:
    In this paper, as a purpose to apply the supersaturated solid-solutionized Al-9Mg alloy to the structural sheet parts of automotive, tensile tests were conducted under the various conditions and a constitutive equation was derived from the tensile test results. Al-9Mg alloy was produced using a special Mg master alloy containing Al2Ca during the casting process and extruded into the sheet. In order to study the deformation behavior of Al-9Mg alloy in warm temperature forming environments, tensile tests were conducted under the temperature of 373 K-573 K and the strain rate of 0.001/s~0.1/s. in addition, by using the raw data obtained from tensile tests, a constitutive equation of the Al-9Mg alloy was derived for predicting the optimized condition of the hot stamping process. Al-9Mg alloy showed uncommon deformation behavior at the 373 K and 473 K temperature conditions. The calculated curves from the constitutive equation well-matched with the measured curves from the experiments particularly under the low temperature and high strain rate conditions.
    Źródło:
    Archives of Metallurgy and Materials; 2021, 66, 4; 1013-1018
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Isotopic water separation using AGMD and VEMD
    Autorzy:
    Kim, J.
    Park, S.
    Kim, T.-S.
    Jeong, D.-Y.
    Ko, K.-H.
    Powiązania:
    https://bibliotekanauki.pl/articles/147314.pdf
    Data publikacji:
    2004
    Wydawca:
    Instytut Chemii i Techniki Jądrowej
    Tematy:
    AGMD
    VEMD
    oxygen isotopes
    PET
    FDG
    Opis:
    The 18O isotopic water permeation and separation characteristics of a hydrophobic PTFE membrane using Air Gap Membrane Distillation (AGMD) and Vacuum Enhanced Membrane Distillation (VEMD) were investigated. Permeation fluxes were measured by weighing the collected membrane-permeated water vapor. 18O/16O of each water sample was analyzed by the Tunable Diode Laser Absorption Spectroscopy (TDLAS). We observed the effects of the air filled membrane pores and the temperature gradient applied to the membrane surfaces on the vapor permeation flux and the oxygen isotope separation for the first time. For both AGMD and VEMD, the permeation flux and the degree of 18O separation increased as the membrane interfacial temperature gradient increased. Even though, oxygen isotope separation and the permeation flux for VEMD is slightly higher than AGMD, the latter may be more efficient from the system's operational point of view.
    Źródło:
    Nukleonika; 2004, 49, 4; 137-142
    0029-5922
    1508-5791
    Pojawia się w:
    Nukleonika
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Variable-Focus Fluid Lens Using an Electromagnetic Actuator
    Autorzy:
    Lee, J.
    Park, K.
    Choi, J.
    Kim, H.
    Kong, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/1399681.pdf
    Data publikacji:
    2013-02
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    85.85.+j
    42.79.Bh
    Opis:
    A variable-focus fluid lens controlled by an electromagnetic actuator and its characteristics are presented in this paper. The repulsive force between an NdFeB magnet and a solenoid through electromagnetic induction causes deflections in the elastomeric membranes integrated in the lens resulting in a focal-length change. The controllability of the focal length of the fabricated lens with an aperture size of 2 mm was approximately from infinity to 15 mm (with input current of 100 mA). The actuator including the solenoid was carefully designed to avoid thermal crosstalk of the lens fluid and magnet from the electromagnetic induction of the solenoid. The settling time to form a convex shape of the lens membrane was approximately 2.5 ms at an input current of 20 mA.
    Źródło:
    Acta Physica Polonica A; 2013, 123, 2; 202-204
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Achene morphology and pericarp anatomy of Anemone, Hepatica, and Pulsatilla (Anemoninae, Ranunculaceae)
    Autorzy:
    Ghimire, B.
    Yum, D.
    Kim, J.H.
    Jeong, M.J.
    Powiązania:
    https://bibliotekanauki.pl/articles/2117680.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czasopisma i Monografie PAN
    Tematy:
    achene
    Anemoninae
    pericarp
    Ranunculaceae
    taxonomy
    Opis:
    The achene morphology and pericarp anatomy of 12 taxa representing three genera (Anemone, Hepatica, and Pulsatilla) of the subtribe Anemoninae were investigated using microtome and light microscopy to evaluate the taxonomic implications of achene characters. The achenes of Anemone were elliptical or obovoid and beaked, whereas the achene of Hepatica and Pulsatilla were obovoid and elliptical, respectively. Noticeable variations in both quantitative and qualitative features of achenes were observed among the species of the three genera. One-way analysis of variance indicated that the quantitative achene variables among the species were highly significant (P<0.001). Pearson’s correlation coefficient also showed a significant correlation between different achene variables. The pericarp structure, particularly the number of cell layers and cell forms in the exocarp and endocarp, seems to be very useful for species delimitation in Anemone and Hepatica. The nature of the endotesta could provide substantial proof for sub-generic classification in Anemone. Unweighted paired group analysis showed the utility of achene features for taxonomic groupings of the species within the studied genera. Although the specimen samples represented a limited range of taxa, the achene features and pericarp anatomy provided a reasonable source for the taxonomic treatment of the studied genera within the subtribe.
    Źródło:
    Acta Biologica Cracoviensia. Series Botanica; 2021, 63, 1; 7-19
    0001-5296
    Pojawia się w:
    Acta Biologica Cracoviensia. Series Botanica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication of Antireflection Structures as a Protective Layer of Solar Cells with Nanoporous Silica Films and Nanoimprinted Moth-Eye Structure
    Autorzy:
    Kim, K.
    Han, J.
    Jang, J.
    Choi, C.
    Choi, S.
    Kim, C.
    Kye, H.
    Cheong, I.
    Powiązania:
    https://bibliotekanauki.pl/articles/1492625.pdf
    Data publikacji:
    2011-12
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    61.46.-w
    68.37.-d
    68.55.-a
    78.20.-e
    Opis:
    The antireflection structures are fabricated by sol-gel process as a protective layer of solar cells and by hot embossing process with anodized aluminum oxide membrane template on polycarbonate film. The optical properties and morphology of the antireflection structures are analyzed by UV-visible spectroscopy and field emission scanning electron microscopy, respectively. The total conversion efficiency of a polycrystalline Si solar cell module with the protective layer, sol-gel-derived nanoporous antireflection structure, is increased by 2.6% and 5.7% for one-side antireflection coated prismatic matt glass and both-side antireflection coated prismatic matt glass, respectively.
    Źródło:
    Acta Physica Polonica A; 2011, 120, 6A; A-047-A-049
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Contamination of soil with heavy metals drained out from abandoned mines in the South-West region of Korea
    Autorzy:
    Kim, S.-D.
    Dho, H.-S.
    Lee, S.-J.
    Powiązania:
    https://bibliotekanauki.pl/articles/207493.pdf
    Data publikacji:
    2015
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    soil pollution
    abandoned mines
    arsenic
    heavy metals
    nickel
    soils
    zinc
    contamination level
    forest regions
    surface soil
    zanieczyszczenie gleby
    zlikwidowane kopalnie
    arsen
    metale ciężkie
    nikiel
    gleby
    cynk
    poziom zanieczyszczeń
    obszary leśne
    powierzchniowe warstwy gleby
    Opis:
    Contamination of soil with heavy metals drained out from twenty eight abandoned mines in the southwest regions of Korea has been investigated. Utilizing various statistical techniques, the goal was to evaluate and analyze pH and the contamination with Arsenic, and the following six heavy metals: cadmium, hydrargyrum, lead, nickel, chromium, and zinc. Contamination levels of heavy metals were determined depending on the depth of the soil. Results indicated that the subsoil and the surface soil both were strongly contaminated with lead and arsenic. Furthermore, the subsoil also contained much nickel. In forest regions, high levels of lead and arsenic, whereas in all regions high levels of zinc have been detected.
    Źródło:
    Environment Protection Engineering; 2015, 41, 3; 61-72
    0324-8828
    Pojawia się w:
    Environment Protection Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Flexible pavement analysis considering temperature profile and anisotropy behavior in hot mix asphalt layer
    Autorzy:
    Choi, J.
    Seo, Y.
    Kim, S. H.
    Beadles, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/230733.pdf
    Data publikacji:
    2011
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    zachowanie anizotropowe
    metoda elementów skończonych
    kruszywo
    nawierzchnia
    HMA
    anisotropic behavior
    finite element method
    aggregate base
    pavement
    Opis:
    A three Dimensional finite element model (FEM) incorporating the anisotropic properties and temperature profile of hot mix asphalt (HMA) pavement was developed to predict the structural responses of HMA pavement subject to heavy loads typically encountered in the field. In this study, ABAQUS was adopted to model the stress and strain relationships within the pavement structure. The results of the model were verified using data collected from the Korean Highway Corporation Test Road (KHCTR). The results demonstrated that both the base course and surface course layers follow the anisotropic behavior and the incorporation of the temperature profile throughout the pavement has a substantial effect on the pavement response predictions that impact pavement design. The results also showed that the anisotropy level of HMA and base material can be reduced to as low as 80% and 15% as a result of repeated loading, respectively.
    Źródło:
    Archives of Civil Engineering; 2011, 57, 4; 347-356
    1230-2945
    Pojawia się w:
    Archives of Civil Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication of AZ31/CNT Surface Nano-composite by Double-pass Friction Stir Processing
    Autorzy:
    Kim, J. Y.
    Hwang, J.-W.
    Kim, H. Y.
    Lee, S. M.
    Jung, W.-S.
    Byeon, J.-W.
    Powiązania:
    https://bibliotekanauki.pl/articles/355624.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    surface modification
    Double-pass Friction Stir Processing
    AZ31
    composite
    CNT
    Opis:
    Double-pass Friction Stir Processing (FSP) was applied to fabricate an AZ31/CNT nano-composite for surface hardening of lightweight structural components. The effects of double-pass FSP as well as groove depth (i.e., volume fraction of CNT) on the CNT distribution, dynamically recrystallized grain size, and resulting microhardness were studied. Double-pass FSP was performed for the CNT-filled plate-type specimen with different groove depths of 2, 3, and 4 mm. By applying double-pass FSP, the average size of CNT clusters decreased, implying a more homogeneous distribution. Compared with the FSPed specimen without CNT, grain size was refined from 19 μm to 3 μm and microhardness increased from 52 Hv to 83 Hv (i.e., 71% increase).
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1039-1042
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication Of Zn4Sb3 Alloys By A Combination Of Gas-Atomization And Spark Plasma Sintering Processes
    Wytwarzanie i konsolidacja proszków stopowych zn4sb3 przez kombinację procesów atomizacji gazowej i spiekania
    Autorzy:
    Dharmaiah, P.
    Kim, H.-S.
    Lee, L. H.
    Hong, S.-J.
    Powiązania:
    https://bibliotekanauki.pl/articles/355894.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    gas atomization
    microstructure
    spark plasma sintering (SPS)
    X-ray diffraction
    atomizacja gazowa
    mikrostruktura
    SPS
    spiekanie plazmowe
    analiza rentgenowska (XRD)
    Opis:
    In this study, single phase polycrystalline Zn4Sb3 as well as 11 at.% Zn-rich Zn4Sb3 alloy having ε-Zn4Sb3 (majority phase) and Zn (minority phase) phases bulk samples produced by gas-atomization and subsequently consolidated by spark plasma sintering (SPS) process. The crystal structures were analyzed by X-ray diffraction (XRD) and cross-sectional microstructure were observed by the scanning electron microscopy (SEM). The internal grain microstructure of 11at.% Zn-rich Zn4Sb3 powders shows lamellar structure. Relative density, Vickers hardness and crack lengths were measured to investigate the effect of sintering temperature of Zn4Sb3 samples which are sintered at 653, 673 and 693 K. Relative density of the single phase bulk Zn4Sb3 sample reached to 99.2% of its theoretical density. The micro Vickers hardness of three different sintering temperatures were found around 2.17 – 2.236 GPa.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1417-1421
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Self-Consolidation and Surface Modification of Mechanical Alloyed Ti-25.0 at.% Al Powder Mixture by Using an Electro-Discharge Technique
    Autorzy:
    Chang, S. Y.
    Jang, H. S.
    Yoon, Y. H.
    Kim, Y. H.
    Kim, J. Y.
    Lee, Y. K.
    Lee, W. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/354212.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    sintering
    mechanical alloying
    powder consolidation
    intermetallic compounds
    titanium aluminides
    Opis:
    Electrical discharges using a capacitance of 450 μF at 0.5, 1.0, and 1.5 kJ input energies were applied in a N2 atmosphere to obtain the mechanical alloyed Ti3Al powder without applying any external pressure. A solid bulk of nanostructured Ti3Al was obtained as short as 160 μsec by the Electrical discharge. At the same time, the surface has been modified into the form of Ti and Al nitrides due to the diffusion process of nitrogen to the surface. The input energy was found to be the most important parameter to affect the formation of a solid core and surface chemistry of the compact.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1293-1297
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Evaluation of Surface Characteristics and Physical Properties on Biodegradable Magnesium-Calcium Alloys by Anodic Oxidation
    Autorzy:
    Kim, J.
    Lee, J.
    Yang, H.
    Park, S.
    Lim, H.
    Oh, G.
    Yun, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/1191716.pdf
    Data publikacji:
    2016-04
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    87.85.jj
    87.85.jc
    Opis:
    The purpose of this study was to determine the effect of calcium (Ca) on the surface characteristics and physical properties of magnesium-calcium alloys after anodization. A novel binary alloy Mg-xCa (in which x=0.5, 1, or 5 wt.%) was cast by combining magnesium (99.9%) and calcium (99.9%) in an argon gas (99.99%) atmosphere. A magnesium alloy rod having a diameter of 15 mm was cut into discs, each 2 mm thick. The specimens were subjected to anodic oxidation at 120 V for 15 minutes at room temperature in an electrolyte solution consisting of calcium gluconate, sodium hexametaphosphate, and sodium hydroxide. Surface and cross-sectional morphological changes were observed using scanning electron microscopy, and the microstructures and phases were detected by means of X-ray diffraction. Hardness and surface roughness were assessed by means of a Vickers hardness tester and a surface roughness meter, respectively. The results show that the physical properties of these magnesium-calcium alloys have been improved, because it was possible to control the dissolution rate according to the amount of calcium added.
    Źródło:
    Acta Physica Polonica A; 2016, 129, 4; 736-741
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Experimental Study On Fracture Property Of Double Cantilever Beam Specimen With Aluminum Foam
    Doświadczalne badanie pękania mimośrodowo rozciąganej próbki z bocznym karbem wykonanej z piany aluminiowej
    Autorzy:
    Kim, Y. C.
    Choi, H. K.
    Cho, J. U.
    Powiązania:
    https://bibliotekanauki.pl/articles/351465.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    aluminium foam
    double cantilever beam
    fracture energy
    adhesively bonded structure
    piana aluminiowa
    podwójna belka wspornikowa
    energia pękania
    Opis:
    This study aims to investigate double cantilever beam specimen with aluminum foam bonded by spray adhesive to investigate the fracture strength of the adhesive joint experimentally. The fracture energy at opening mode is calculated by the formulae of British Engineering Standard (BS 7991) and International Standard (ISO 11343). For the static experiment, four types of specimens with the heights (h) of 25 mm, 30 mm, 35 mm and 40 mm are manufactured and the experimental results are compared with each other. As the height becomes greater, the fracture energy becomes higher. After the length of crack reaches 150 mm, the fracture energy of the specimen (h=35 mm) is greater than that of the specimen (h=40 mm). Fatigue test is also performed with DCB test specimen. As the height decreases, the fracture energy becomes higher. By the result obtained from this study, aluminum foam with adhesive joint can be applied to actual composite structure and its fracture property can possibly be anticipated.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1151-1154
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Novel Extraction Process Of Rare Earth Elements From NdFeB Powders Via Alkaline Treatment
    Nowy sposób ekstrakcji pierwiastków ziem rzadkich z proszków NdFeB w roztworach alkalicznych
    Autorzy:
    Chung, K. W.
    Kim, C.-J.
    Yoon, H.-S.
    Powiązania:
    https://bibliotekanauki.pl/articles/355324.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    recycling
    NdFeB magnet
    alkaline treatment
    leaching
    selective leaching efficiency
    recykling
    magnes neodymowy
    obróbka alkaliczna
    ługowanie
    wydajność
    Opis:
    The alkaline treatment of NdFeB powders in NaOH solution at various equivalent amounts of NaOH at 100°C was performed. The resultant powders were then leached in 0.5M H2SO4 solution at 25°C for 2 minutes. At 5 equivalents of NaOH, neodymium in NdFeB powders was partially transformed to neodymium hydroxide. The transformation of neodymium to neodymium hydroxide actually occurred at 10 equivalents of NaOH and was facilitated by increasing the equivalent of NaOH from 10 to 30. In addition, iron was partially transformed to magnetite during the alkaline treatment, which was also promoted at a higher equivalent of NaOH. The leaching yield of neodymium from alkaline-treated powders was increased with an increasing equivalent of NaOH up to 10; however, it slightly decreased with the equivalent NaOH of over 10. The leaching yield of iron was inversely proportional to that of rare earth elements. NdFeB powders treated at 10 equivalents of NaOH showed a maximum leaching yield of neodymium and dysprosium of 91.6% and 94.6%, respectively, and the lowest leaching yield of iron of 24.2%, resulting in the highest selective leaching efficiency of 69.4%.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1301-1305
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Characterization Of The Graded Microstructure In Powder Sintered Porous Titanium
    Charakterystyka gradientowej mikrostruktury porowatego tytanu spiekanego z proszku
    Autorzy:
    Oak, J.-J.
    Bang, J. I.
    Bae, K.-C.
    Kim, Y. H.
    Lee, Y. C.
    Chun, H. H.
    Park, Y. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/356239.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    titanium
    powder metallurgy
    porous structure
    sintering
    biomaterial
    tytan
    metalurgia proszków
    struktura porowata
    spiekanie
    biomateriał
    Opis:
    The proposed sintering process produce porosity and functional graded microstructure in the sinterd titanium powders. Titanium powders with different micro sizes were sintered at the proposed temperature region at 1200 and 1300°C for 2h. The apatite-forming on the graded microstructure is observed by immersion test in Hanks balanced salt soluion at 37°C. Sintering condition of titanium powders is estimated by thermogravitmetry-differential thermal analysis (TG-DTA). The synthersied surface structures and apatite-forming ability were characterized by a field emission scanning electron microscopy (FE-SEM) observation and energy dispersive X-ray spectroscopy (EDS) analysis. As results, these graded microstructure of sintered porous titanium powders reveals apatite-forming ability as osseointegration by calcification in Hanks balanced salt soluion(HBSS) at 37°C.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1265-1269
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Preparation Of Fine Grained SiC At Reduced Temperature By Two-Step Sintering
    Wytwarzanie drobnoziarnistego SiC w obniżonej temperaturze przez dwuetapowe spiekanie
    Autorzy:
    Kim, K.-W.
    Oh, K.-S.
    Lee, H.
    Kim, B. S.
    Chung, T.-J.
    Powiązania:
    https://bibliotekanauki.pl/articles/353772.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    SiC
    liquid phase
    two step sintering
    coarsening
    hardness
    faza ciekła
    spiekanie dwuetapowe
    odporność
    twardość
    Opis:
    Two-step sintering route was applied for the densification SiC by promoting the role of liquid phase. The specimen contained 8 vol% of liquid phase composed of Al2O3 and Y2O3. The heating schedule consisted with initial rapid heating to 2000°C and immediate quenching to 1700 or 1750°C. By heating at elevated temperature, even distribution of the liquid phase was intended. The heat treatment at reduced temperature was to suppress the evaporative loss of the liquid and to secure the time for densification. The two-step sintering effectively suppressed loss of mass and coarsening. The resultant SiC was thus dense and was composed of fine grains exhibiting hardness of 2321 kgf/mm2.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1539-1542
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Surface Modification of Self-Consolidated Microporous Ti Implant Compacts Fabricated by Electro-Discharge-Sintering in Air
    Autorzy:
    Jo, Y. J.
    Yoon, Y. H.
    Kim, Y. H.
    Chang, S. Y.
    Kim, J. Y.
    Lee, Y. K.
    Van Tyne, C. J.
    Lee, W. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/356790.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    titanium
    implant
    porous
    sintering
    X-ray photoelectron spectroscopy (XPS)
    Opis:
    A single pulse of 0.75-2.0 kJ/0.7g of atomized spherical Ti powders from 300 mF capacitor was applied to produce a microporous Ti implant compact by electro-discharge-sintering (EDS). A solid core in the middle of the compact surrounded by a microporous layer was found. X-ray photoelectron spectroscopy was employed to study the surface characteristics of the EDS Ti compact and it revealed that Ti, C and O were the main constituents on the surface with a smaller amount of N. The surface was lightly oxidized and was primarily in the form of TiO2 resulting from the air oxidation during EDS processing. The lightly oxidized surface of the EDS compact also exhibited Ti nitrides such as TiN and TiON, which revealed that the reaction between air constituents and the Ti powders even in times as short as 128 msec.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1287-1291
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Photoluminescence Studies of Aluminum Nitride Nanowires
    Autorzy:
    Yang, J.
    Na, H.
    Kim, H.
    Kebede, M.
    Choi, R.
    Jeong, J.
    Lee, C.
    Powiązania:
    https://bibliotekanauki.pl/articles/1505466.pdf
    Data publikacji:
    2011-02
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    81.07.-b
    78.55.-m
    Opis:
    We report the production of AlN nanowires by the thermal heating method, for exploring their photoluminescence properties. The room-temperature photoluminescence properties were investigated with different annealing environment. While broad emissions with peaks at around 2.45 and 2.95 eV were obtained from both unannealed and annealed samples, the additional 2.1 eV peak was found from the annealed samples. We have suggested the possible emission mechanisms based on the assumption that both 2.45 eV peak and 2.1 eV peak are ascribed to the nitrogen vacancies. Annealing in N_2 environment exhibited lower intensities of 2.45 eV peak and 2.1 eV peak in comparison to those in Ar environment, presumably due to the suppression of nitrogen vacancies.
    Źródło:
    Acta Physica Polonica A; 2011, 119, 2; 125-127
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis and Optimization of Micro Speaker-Box Using a Passive Radiator in Portable Device
    Autorzy:
    Jiang, Y.-W.
    Kwon, J.-H.
    Kim, H.-K.
    Hwang, S.-M.
    Powiązania:
    https://bibliotekanauki.pl/articles/176530.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    passive radiator
    speaker box
    SPL improvement
    Sound Pressure Level
    Opis:
    With the rapid development of multimedia devices such as smart phones and tablet PCs, microspeakers have been recently increasingly used for audio equipment. Improving the acoustic performance of a microspeaker is always a main concern, especially in the low frequency range. To avoid sound cancelation, a microspeaker unit is usually inserted into a speaker box. A passive radiator is also used in speaker boxes to improve the sound performance in the loudspeaker system. However, passive radiators have not been applied into microspeaker system. In this study, a speaker box with a passive radiator was analyzed and optimized to achieve a higher Sound Pressure Level (SPL) in a microspeaker system. The Finite Element Method (FEM), two-degree-of-freedom (DOF) vibration theory, and a plane circular piston sound source were used to study the electromagnetic, vibration, and acoustic characteristics, respectively. Optimization was conducted by changing the mass, stiffness, and size of the passive radiator. Based on the optimized parameters, a new sample was manufactured. The experiment results show that the SPL of the optimized speaker box with a passive radiator is improved by 5 dB at 200 Hz compared with the one without a radiator. The analysis results also matched the experiment results.
    Źródło:
    Archives of Acoustics; 2017, 42, 4; 753-760
    0137-5075
    Pojawia się w:
    Archives of Acoustics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A mixed control chart adapted to the truncated life test based on the Weibull distribution
    Autorzy:
    Khan, N.
    Aslam, M.
    Kim, K.-J.
    Jun, C. -H.
    Powiązania:
    https://bibliotekanauki.pl/articles/406432.pdf
    Data publikacji:
    2017
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    life test
    Weibull distribution
    attribute chart
    binomial distribution
    average run length
    Opis:
    The design of a new mixed attribute control chart adapted to a truncated life test has been pre-sented. It was assumed that the lifetime of a product follows the Weibull distribution and the number of failures was observed using a truncated life test, where the test duration was specified as a fraction of the mean lifespan. The proposed control chart consists of two pairs of control limits based on a binomial distribution and one lower bound. The average run length of the chart was determined for various levels of shift constants and specified parameters. The efficiency of the chart is compared with an existing control chart in terms of the average run length. The application of the proposed chart is discussed with the aid of a simulation study.
    Źródło:
    Operations Research and Decisions; 2017, 27, 1; 43-55
    2081-8858
    2391-6060
    Pojawia się w:
    Operations Research and Decisions
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Long-term effect of niclosamide on inhibition of bacterial leaf blight in rice
    Autorzy:
    Kim, S.-I.
    Kwak, J.S.
    Song, J.T.
    Seo, H.S.
    Powiązania:
    https://bibliotekanauki.pl/articles/65390.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    long-term effect
    niclosamide
    niclocide zob.niclosamide
    inhibition
    bacterial disease
    leaf disease
    rice
    bacterial blight disease
    Xanthomonas oryzae pv.oryzae
    Opis:
    Bacterial leaf blight is one of the major diseases in rice and affects yields. Thus, various methods have been applied to protect rice from this disease. Here, we show systemic translocation of the human drug niclosamide (5-chloro-N-(2-chloro-4-nitrophenyl)- 2-hydroxybenzamide) in rice and its long-term effect on prevention of rice leaf blight. The development of Xanthomonas oryzae pv. oryzae-induced rice leaf blight was effectively inhibited in untreated systemic leaves as in niclosamide-treated leaves, although its effect gradually decreased in a time-dependent manner. Time-course examination after niclosamide treatment showed that the niclosamide level was highest after 3 h in non-treated distal leaves, suggesting fast systemic movement of niclosamide from the treated local site to untreated distal regions. Our data indicate that niclosamide controls rice leaf blight by its rapid systemic movement and that its effect is maintained for a long time.
    Źródło:
    Journal of Plant Protection Research; 2016, 56, 4
    1427-4345
    Pojawia się w:
    Journal of Plant Protection Research
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Formation And Stabilization Of Silver Nanoparticles In Ethanol By Phosphinic Acid
    Redukcja i stabilizacja nanocząstek srebra w etanolu przez kwas fosforowy
    Autorzy:
    Kim, J.-K.
    Shim, H.-M.
    Park, M. J.
    Koo, K.-K.
    Powiązania:
    https://bibliotekanauki.pl/articles/356073.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    silver
    nanoparticle
    kinetic analysis
    phosphinic acid
    reduction
    srebro
    nanocząstki
    analiza kinetyczna
    kwas fosforowy
    redukcja
    Opis:
    Although phosphinic acid (H3PO2) has a powerful reduction potential, the reduction of silver ions by phosphinic acid salt has not yet been reported. In this work, colloidal silver has successfully synthesized by reducing silver ions in ethanol with phosphinic acid as a reducing agent. The effects of [AgNO3]/[H3PO2] ratios and reaction temperature were considered. Spherical silver nanoparticles with cubic structure were successfully prepared and their diameters were measured to be 8.5±0.9 nm − 11.3±0.2 nm. Half-life analysis showed that the reduction of silver ions proceeded with the reaction order of 1.30 on concentration of phosphinic acid and activation energy of 120.7 kJ/mol.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1293-1296
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Trace Elements (Co, Cr) on the Microstructure and Physical Properties of Al-Si-Cu-Mg-Fe Extruded Alloy
    Autorzy:
    Ahn, S. S.
    Sharief, P.
    Lee, C. H.
    Son, H. T.
    Kim, Y. H.
    Kim, Y. C.
    Hong, S.
    Hong, S. J.
    Powiązania:
    https://bibliotekanauki.pl/articles/352787.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Al-Si alloy
    microstructure
    extrusion
    coefficient of thermal expansion
    trace elements
    Opis:
    Trace elements Co, Cr were added to investigate their influence on the microstructure and physical properties of Al-Si extruded alloy. The Co, Cr elements were randomly distributed in the matrix, forms intermetallic phase and their existence wereconfirmed by XRD, EDS and SEM analysis. With addition of trace elements, the microstructure was modified, Si particle size was reduced and the growth rate of β-(Al5 FeSi) phase limited. Compared to parent alloy, hardness and tensile strength were enhanced while the linear coefficient of thermal expansion (CTE) was significantly reduced by 42.4% and 16.05% with Co and Cr addition respectively. It is considered that the low CTE occurs with addition of Co was due to the formation of intermetallic compound having low coefficient of thermal expansion. The results suggested that Co acts as an effective element in improving the mechanical properties of Al-Si alloy.
    Źródło:
    Archives of Metallurgy and Materials; 2019, 64, 3; 857-862
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Self-Consolidation Mechanism of Ti5Si3 Compact Obtained by Electro-Discharge-Sintering Directly from Physically Blended Ti-37.5 At.% Si Powder Mixture
    Autorzy:
    Chang, S. Y.
    Cheon, Y. W.
    Yoon, Y. H.
    Kim, Y. H.
    Kim, J. Y.
    Lee, Y. K.
    Lee, W. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/353022.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    sintering
    mechanical alloying
    powder consolidation
    intermetallic compounds
    titanium silicide
    Opis:
    Characteristics of electro-discharge-sintering of the Ti-37.5at.% Si powder mixture was investigated as a function of the input energy, capacitance, and discharge time without applying any external pressure. A solid bulk of Ti5Si3 was obtained only after in less than 129 μsec by the EDS process. During a discharge, the heat is generated to liquefy and alloy the particles, and which enhances the pinch pressure can condensate them without allowing a formation of pores. Three step processes for the self-consolidation mechanism during EDS are proposed; (a) a physical breakdown of oxide film on elemental as-received powder particles, (b) alloying and densifying the consolidation of powder particles by the pinch pressure, and (c) diffusion of impurities into the consolidated surface.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1299-1302
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Compositional Dependence of Hardness of Ge-Sb-Se Glass for Molded Lens Applications
    Zależność stężeniowa twardości szkła Ge-Sb-Se do zastosowań na formowane soczewki
    Autorzy:
    Park, J. K.
    Lee, J. H.
    Shin, S. Y.
    Yi, J. H.
    Lee, W. H.
    Park, B. J.
    Choi, J. H.
    Kim, N. Y.
    Choi, Y. G.
    Powiązania:
    https://bibliotekanauki.pl/articles/352228.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    chalcogenide glasses
    Ge-Sb-Se glass
    infrared lens
    molded lens
    infrared camera
    szkło
    Ge-Sb-Se
    soczewki formowane
    twardość szkła
    kamera termowizyjna
    Opis:
    Chalcogenide glass in the ternary Ge-Sb-Se system is inherently moldable, thus being considered as a strong candidate material for use in infrared-transmitting lens applications from the viewpoint of thermal and mechanical stability. In an effort to experimentally determine compositional region suitable for the molded lens applications, we evaluate its compositional dependence of hardness. Among the constituent atoms, Ge content turns out to exert a most conspicuous correlation with hardness. This phenomenological behavior is then explained in connection with the structural evolution that Ge brings about.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1205-1208
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Recovery Of Electrodic Powder From Spent Nickel-Metal Hydride Batteries (NiMH)
    Odzyskiwanie proszku elektrodowego ze zużytych akumulatorów niklowo-wodorkowych (NiMH)
    Autorzy:
    Shin, S. M.
    Shin, D. J.
    Jung, G. J.
    Kim, Y. H.
    Wang, J. P.
    Powiązania:
    https://bibliotekanauki.pl/articles/356110.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    nickel-metal hybride (NiMH)
    electrodic powder
    nickel
    rare earth elements (REE)
    thermal treatment
    akumulator niklowo-wodorkowy
    proszek elektrodowy
    nikiel
    pierwiastki ziem rzadkich
    obróbka termiczna
    Opis:
    This study was focused on recycling process newly proposed to recover electrodic powder enriched in nickel (Ni) and rare earth elements (La and Ce) from spent nickel-metal hydride batteries (NiMH). In addition, this new process was designed to prevent explosion of batteries during thermal treatment under inert atmosphere. Spent nickel metal hydride batteries were heated over range of 300°C to 600°C for 2 hours and each component was completely separated inside reactor after experiment. Electrodic powder was successfully recovered from bulk components containing several pieces of metals through sieving operation. The electrodic powder obtained was examined by X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX) and image of the powder was taken by scanning electron microscopy (SEM). It was finally found that nickel and rare earth elements were mainly recovered to about 45 wt.% and 12 wt.% in electrodic powder, respectively.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1139-1143
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Studies on the effect of coal particle size on biodepyritization of high sulfur coal in batch bioreactor
    Autorzy:
    Singh, S.
    Srichandan, H.
    Pathak, A.
    Gahan, Ch. S.
    Lee, S.
    Kim, D. J.
    Kim, B. G.
    Powiązania:
    https://bibliotekanauki.pl/articles/778523.pdf
    Data publikacji:
    2015
    Wydawca:
    Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
    Tematy:
    biodepyritization
    coal
    pyrite
    stirred tank bioreactor
    Opis:
    The moderate thermophilic mix culture bacteria were used to depyritize the Illinois coal of varying particle sizes (-100 μm, 100-200 μm, +200 μm). Mineral libration analysis showed the presence of pyrite along with other minerals in coal. Microbial depyritization of coal was carried out in stirred tank batch reactors in presence of an iron-free 9K medium. The results indicate that microbial depyritization of coal using moderate thermophiles is an efficient process. Moreover, particle size of coal is an important parameter which affects the efficiency of microbial depyritization process. At the end of the experiment, a maximum of 75% pyrite and 66% of pyritic sulphur were removed from the median particle size. The XRD analysis showed the absence of pyrite mineral in the treated coal sample. A good mass balance was also obtained with net loss of mass ranging from 5-9% showing the feasibility of the process for large scale applications.
    Źródło:
    Polish Journal of Chemical Technology; 2015, 17, 1; 97-102
    1509-8117
    1899-4741
    Pojawia się w:
    Polish Journal of Chemical Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Characterization of Cu and Ni Nano-Fluids Synthesized by Pulsed Wire Evaporation Method
    Autorzy:
    Kim, H.-S.
    Yilmaz, F.
    Dharmaiah, P.
    Lee, D.-J
    Lee, T.-H.
    Hong, S.-J.
    Powiązania:
    https://bibliotekanauki.pl/articles/356475.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    pulsed wire evaporation
    nanofluid
    Cu
    Ni
    suspension stability
    dispersibility
    Opis:
    In the present work, Cu and Ni nanofluids were synthesized using the pulsed wire evaporation (PWE) method in the different aqueous medias, namely (ethanol and ethylene glycol), and the effects of the aqueous media on the dispersion state, stability, and particle size of nanoparticles were studied. The size and morphology of synthesized nano-particles were investigated by transmission electron microscopy (TEM). Also, the dispersion stability of the nanofluids was evaluated by turbiscan analysis. The TEM results showed that the nano-particles were spherical in shape, and the average particle size was below 100 nm. The average particle size of the Cu nano-particles was smaller than that of Ni, which was attributed to a difference in the specific sublimation energy of the elements. Moreover, ethylene glycol (EG) exhibited higher suspension stability than ethanol. Finally, the dispersion stability of Cu@EG displayed the highest value due to lower particle size and greater viscosity.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 999-1004
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Synthesis And Electrochemical Characteristics Of Mechanically Alloyed Anode Materials SnS2 For Li/SnS2 Cells
    Synteza mechaniczna i charakterystyka elektrochemiczna materiałów anodowych SnS2 dla ogniw Li/SnS2
    Autorzy:
    Hong, J. H.
    Liu, X. J.
    Park, D. K.
    Kim, K. W.
    Ahn, H. J.
    Ahn, I. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/356903.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    MA
    Li/SnS2 cell
    PCA
    wet milling process and electrochemical characteristics
    ogniwa Li/SnS2
    charakterystyka elektromechaniczna
    Opis:
    With the increasing demand for efficient and economic energy storage, tin disulfide (SnS2), as one of the most attractive anode candidates for the next generation high-energy rechargeable Li-ion battery, have been paid more and more attention because of its high theoretical energy density and cost effectiveness. In this study, a new, simple and effective process, mechanical alloying (MA), has been developed for preparing fine anode material tin disulfides, in which ammonium chloride (AC), referred to as process control agents (PCAs), were used to prevent excessive cold-welding and accelerate the synthesis rates to some extent. Meanwhile, in order to decrease the mean size of SnS2 powder particles and improve the contact areas between the active materials, wet milling process was also conducted with normal hexane (NH) as a solvent PCA. The prepared powders were both characterized by X-ray diffraction, Field emission-scanning electron microscopeand particle size analyzer. Finally, electrochemical measurements for Li/SnS2 cells were takenat room temperature, using a two-electrode cell assembled in an argon-filled glove box and the electrolyte of 1M LiPF6 in a mixture of ethylene carbonate(EC)/dimethylcarbonate (DMC)/ethylene methyl carbonate (EMC) (volume ratio of 1:1:1).
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1191-1194
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect Of SiC Particles On Sinterability Of Al-Zn-Mg-Cu P/M Alloy
    Wpływ cząstek SiC na spiekalność proszku stopowego Al-Zn-Mg-Cu
    Autorzy:
    Rudianto, H.
    Jang, G. J.
    Yang, S. S.
    Kim, Y. J.
    Dlouhy, I.
    Powiązania:
    https://bibliotekanauki.pl/articles/351304.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    metal matrix composites
    powder metallurgy
    sintering
    heat treatment
    kompozyty metalowe
    metalurgia proszków
    spiekanie
    obróbka cieplna
    Opis:
    Premix Al-5.5Zn-2.5Mg-0.5Cu alloy powder was analyzed as matrix in this research. Gas atomized powder Al-9Si with 20% volume fraction of SiC particles was used as reinforcement and added into the alloy with varied concentration. Mix powders were compacted by dual action press with compaction pressure of 700 MPa. High volume fraction of SiC particles gave lower green density due to resistance of SiC particles to plastic deformation during compaction process and resulted voids between particles and this might reduce sinterability of this mix powder. Sintering was carried out under ultra high purity nitrogen gas from 565°-580°C for 1 hour. High content of premix Al-5.5Zn-2.5Mg-0.5Cu alloy powder gave better sintering density and reached up to 98% relative. Void between particles, oxide layer on aluminum powder and lower wettability between matrix and reinforcement particles lead to uncompleted liquid phase sintering, and resulted on lower sintering density and mechanical properties on powder with high content of SiC particles. Mix powder with wt90% of Alumix 431D and wt10% of Al-9Si-vf20SiC powder gave higher tensile strength compare to another mix powder for 270 MPa. From chemical compositions, sintering precipitates might form after sintering such as MgZn2, CuAl2 and Mg2Si. X-ray diffraction, DSC-TGA, and SEM were used to characterize these materials.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1383-1385
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Correlation Between Superheated Liquid Fragility And Onset Temperature Of Crystallization For Al-Based Amorphous Alloys
    Korelacja między krytycznymi parametrami cieczy i temperaturą początku krystalizacji dla amorficznych stopów na bazie Al
    Autorzy:
    Guo, J.
    Hu, X.
    Liu, J.
    Feng, T.
    Yoon, E. Y.
    Kim, H. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/353707.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    superheated liquid fragility
    onset temperature of crystallization
    thermal stability
    krytyczny parametr cieczy
    temperatura początku krystalizacji
    stabilność termiczna
    Opis:
    Amorphous alloys or metallic glasses have attracted significant interest in the materials science and engineering communities due to their unique physical, mechanical, and chemical properties. The viscous flow of amorphous alloys exhibiting high strain rate sensitivity and homogeneous deformation is considered to be an important characteristic in thermoplastic forming processes performed within the supercooled liquid region because it allows superplastic-like deformation behavior. Here, the correlation between the superheated liquid fragility, and the onset temperature of crystallization for Al-based alloys, is investigated. The activation energy for viscous flow of the liquid is also investigated. There is a negative correlation between the parameter of superheated liquid fragility and the onset temperature of crystallization in the same Al-based alloy system. The activation energy decreases as the onset temperature of crystallization increases. This indicates that the stability of a superheated liquid can affect the thermal stability of the amorphous alloy. It also means that a liquid with a large superheated liquid fragility, when rapidly solidified, forms an amorphous alloy with a low thermal stability.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1543-1546
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Specific Heat of RBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-x}$ and RBaSrCu$\text{}_{3}$O$\text{}_{7-x}$ Compounds (R = Sm, Dy, Er)
    Autorzy:
    Tarnawski, Z.
    Kim-Ngan, N.-T. H.
    Wang, X. Z.
    Duijn, V. H. M.
    Franse, J. J. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/1968860.pdf
    Data publikacji:
    1998-03
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    74.70.-b
    75.40.-s
    Opis:
    The low-temperature specific-heat C(T) data of high-T$\text{}_{c}$ superconductors RBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-x}$(R123O$\text{}_{7-x}$) were reviewed. A discussion of the C(T) data obtained on single-crystalline samples of Er123O$\text{}_{7-x}$ and Sm123O$\text{}_{7-x}$ compounds in applied magnetic fields for better evaluation of the crystal-electric-field parameters is given. The C(T) measurements of Sr-substituted compounds RBaSrCu$\text{}_{3}$O$\text{}_{7}$ revealed the λ-type of peak related to the antiferromagnetic order at 1.2 K and 0.6 K respectively for Dy- and Er-compounds. The magnetic singlet ground state in these compounds is produced by weak exchange interactions of -0.05 T/μ$\text{}_{B}$ and -0.035 T/μ$\text{}_{B}$, respectively. For Nd- and Sm-compounds, only a broad anomaly around 0.6 K was observed which is well fitted with a Schottky-type anomaly with an energy splitting of 1.4 K.
    Źródło:
    Acta Physica Polonica A; 1998, 93, 3; 513-522
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication of High-Strength Gray Cast Iron Using Permanent Magnet Scrap
    Autorzy:
    Park, S.-Y.
    Kim, J. H.
    Seo, S. J.
    On, J. S.
    Lim, K. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/352204.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    gray cast iron
    rare earth element
    Nd-Fe-B magnet scrap
    graphite formation
    microstructure
    Opis:
    In this study, we have developed the manufacturing technology for high strength gray cast irons by using the spent permanent magnet scraps. The cast specimen inoculated by using a spent magnet scraps showed the excellent tensile strength up to 306MPa. This tensile strength value is 50MPa higher than that of the specimen cast without inoculation, and is similar to that of the specimen inoculated by using the expensive misch-metal. These superior mechanical properties are attributed to complex sulfides created during solidification that promote the formation and growth of Type-A graphite. It is therefore concluded that spent magnets scrap can provide an efficient and cost-effective inoculation agent for the fabrication of high-performance gray cast iron.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1113-1117
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    High Temperature Oxidation Property of SiC Coating Layer Fabricated by Aerosol Deposition Process
    Autorzy:
    Ham, G.-S.
    Kim, S.-H.
    Park, J.-Y.
    Lee, K.-A.
    Powiązania:
    https://bibliotekanauki.pl/articles/352142.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    silicon carbide
    aerosol deposition
    coating
    high temperature oxidation
    Opis:
    This study investigated the high temperature oxidation property of SiC coated layer fabricated by aerosol deposition process. SiC coated layer could be successfully manufactured by using pure SiC powders and aerosol deposition on the Zr based alloy in an optimal process condition. The thickness of manufactured SiC coated layer was measured about 5 μm, and coating layer represented high density structure. SiC coated layer consisted of α-SiC and β-SiC phases, the same as the initial powder. The initial powder was shown to have been crushed to the extent and was deposited in the form of extremely fine particles. To examine the high temperature oxidation properties, oxidized weight gain was obtained for one hour at 1000°C by using TGA. The SiC coated layer showed superior oxidation resistance property than that of Zr alloy (substrate). The high temperature oxidation mechanism of SiC coated layer on Zr alloy was suggested. And then, the application of aerosol deposited SiC coated layer was also discussed.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1347-1351
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Self-Consolidation Mechanism Of Porous Ti-6Al-4V Implant Prototypes Produced By Electro-Discharge-Sintering Of Spherical Ti-6Al-4V Powders
    Mechanizm autokonsolidacji prototypów porowatych implantów wytworzonych przez spiekanie sferycznych proszków Ti-6Al-4V
    Autorzy:
    Lee, W. H.
    Jo, Y. J.
    Kim, Y. H.
    Jo, Y. H.
    Seong, J. G.
    Van Tyne, C. J.
    Chang, S. Y.
    Powiązania:
    https://bibliotekanauki.pl/articles/356277.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Ti-6Al-4V
    implant
    porous
    sintering
    electrodischarge
    porowatość
    spiekanie
    proszki spiekane
    Opis:
    Electro-Discharge-Sintering (EDS) was employed to fabricate Ti-6Al-4V porous implant prototypes from atomized powders (100 – 150 μm), that were subjected to discharges of 0.75 to 2.0 kJ/0.7g-powder from 150, 300, and 450 μF capacitors. Both fully porous and porous-surfaced Ti-6Al-4V compacts with various solid core sizes were self-consolidated in less than 86 – 155 μsec. It is known that EDS can simultaneously produce the pinch pressure to squeeze and deform powder particles and the heat to weld them together. The formation of a solid core in these prototypes depends on the amounts of both the pinch pressure and heat generated during a discharge. The size of the solid core and the thickness of the porous layer can be successfully controlled by manipulating the discharge conditions such as input energy and capacitance.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1185-1189
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication and Characterization of CoCrFeNiMn High Entropy Alloy Powder Processed by Gas Atomization
    Autorzy:
    Park, T. G.
    Lee, S. H.
    Lee, B.
    Cho, H. M.
    Choi, W. J.
    Kim, B. S.
    Shin, K. S.
    Kim, T.-S.
    Powiązania:
    https://bibliotekanauki.pl/articles/353649.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    high entropy alloy
    gas atomization
    spark plasma sintering
    CoCrFeNiMn
    Opis:
    In this study, precisely controlled large scale gas atomization process was applied to produce spherical and uniform shaped high entropy alloy powder. The gas atomization process was carried out to fabricate CoCrFeNiMn alloy, which was studied for high ductility and mechanical properties at low temperatures. It was confirmed that the mass scale, single phase, equiatomic, and high purity spherical high entropy alloy powder was produced by gas atomization process. The powder was sintered by spark plasma sintering process with various sintering conditions, and mechanical properties were characterized. Through this research, we have developed a mass production process of high quality and spherical high entropy alloy powder, and it is expected to expand applications of this high entropy alloy into fields such as powder injection molding and 3D printing for complex shaped components.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 2; 1055-1059
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Surface Characterization of Metallic Fuel Slugs Prepared by Modified Injection Casting
    Autorzy:
    Mun, S.-U.
    Kim, K.-H.
    Oh, S.-J.
    Park, J.-Y.
    Hong, S.-I.
    Powiązania:
    https://bibliotekanauki.pl/articles/351428.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    sodium-cooled fast reactor
    metallic fuel slug
    U-Zr alloy
    surface characterization
    injection casting
    Opis:
    Metallic fuel slugs containing rare-earth (RE) elements have high reactivity with quartz (SiO2) molds, and a reaction layer with a considerable thickness is formed at the surface of metallic fuel slugs. The surface characterization of metallic fuel slugs is essential for safety while operating a fast reactor at elevated temperature. Hence, it is necessary to evaluate the surface characteristics of the fuel slugs so that chemical interaction between fuel slug and cladding can be minimized in the reactor. When the Si element causes a eutectic reaction with the cladding, it deteriorates the metallic fuel slugs. Thus, it is necessary to examine the characteristics of the surface reaction layer to prevent the reaction of the metallic fuel slugs. In this study, we investigated the metallurgical characteristics of the surface reaction layer of fabricated U-10wt.%Zr-Xwt.%RE (X = 0, 5, 10) fuel slugs using injection casting. The results showed that the thickness of the surface reaction layer increased as the RE content of the metallic fuel slugs increased. The surface reaction layer of the metallic fuel slug was mainly formed by RE, Zr and the Si, which diffused in the quartz mold.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 2; 1049-1053
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Growth of NdBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$ Superconducting Thin Films on SrTiO$\text{}_{3}$(100) and LaSrGaO$\text{}_{4}$(100) Substrates
    Autorzy:
    Park, J.-C.
    Ha, D. H.
    Kim, I.-S.
    Park, Y.K.
    Powiązania:
    https://bibliotekanauki.pl/articles/1964239.pdf
    Data publikacji:
    1997-07
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    74.76.Bz
    Opis:
    NdBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$ superconducting thin films were grown on SrTiO$\text{}_{3}$(100) and LaSrGaO$\text{}_{4}$(100) substrates by off-axis rf sputtering and pulsed laser deposition. The effects of several deposition parameters, e.g. gas pressure, substrate temperature and energy density were studied. Thin films grown by off-axis rf sputtering were highly c-axis oriented, but those by pulsed laser deposition were predominantly a-axis oriented under our deposition conditions. However, the c-axis oriented portion for the films grown by pulsed laser deposition was increased by increasing the temperature above 800°C. T$\text{}_{c(zero)}$ was 87 K and 83 K for the c- and a-axis oriented films respectively. The critical current density of c-axis oriented films was 10$\text{}^{6}$-10$\text{}^{7}$ A/cm$\text{}^{2}$ below 60 K.
    Źródło:
    Acta Physica Polonica A; 1997, 92, 1; 105-114
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Microstructure Evolution of Ni-Based ODS Superalloy Powders During Horizontal Rotary Ball Milling
    Autorzy:
    Lee, H.-E.
    Kim, Y. S.
    Park, J. K.
    Oh, S.-T.
    Powiązania:
    https://bibliotekanauki.pl/articles/355552.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    high energy ball milling
    Ni-base ODS superalloy
    particle and crystalline size
    microstructure
    Opis:
    Microstructure evolution of Ni-based oxide dispersion-strengthened alloy powders with milling time is investigated. The elemental powders having a nominal composition of Ni-15Cr-4.5Al-4W-2.5Ti-2Mo-2Ta-0.15Zr-1.1Y2O3 in wt % were ball-milled by using horizontal rotary ball milling with the change of milling velocity. Microstructure observation revealed that large aggregates were formed in the early stages of ball milling, and further milling to 5 h decreased particle size. The average crystalline size, estimated by the peak broadening of XRD, decreased from 28 nm to 15 nm with increasing milling time from 1 h to 5 h. SEM and EPMA analysis showed that the main elements of Ni and Cr were homogeneously distributed inside the powders after ball milling of 5 h.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1253-1255
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Thermal Conductivity and Microstructure of Copper Coated Graphite Composite by Spark Plasma Sintering Process
    Autorzy:
    Park, S. H.
    Kim, D. B.
    Lee, R. G.
    Son, I. J.
    Powiązania:
    https://bibliotekanauki.pl/articles/355632.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    metal matrix composites
    thermal conductivity
    thermal expansion
    interfacial bonding
    spark plasma sintering
    Opis:
    This study focuses on the fabrication of thermal management material for power electronics applications using graphite flake reinforced copper composites. The manufacturing route involved electroless plating of copper in the graphite flake and sintering process are optimized. The microstructures, interface, thermal properties, and relative density of graphite/Cu composites are investigated. The relative density of the composites shows 99.5% after sintering. Thermal conductivities and coefficients of thermal expansion of this composites were 400-480 Wm-1K-1 and 8 to 5 ppm k-1, respectively. Obtained graphite nanoplatelets-reinforced composites exhibit excellent thermo-physical properties to meet the heat dispersion and matching requirements of power electronic devices to the packaging materials.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1303-1306
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Biological Evaluation of Anodized Biodegradable Magnesium-Calcium Alloys
    Autorzy:
    Kim, J.
    Lee, J.
    Lee, K.
    Park, S.
    Lim, H.
    Park, C.
    Bae, J.
    Yun, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/1398763.pdf
    Data publikacji:
    2016-04
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    87.85.jj
    87.85.J-
    Opis:
    The objective of this study was to evaluate the biocompatibility of studied binary magnesium-calcium (Mg-Ca) alloys for biodegradable intraosseous implants. Mg is necessary for health and is a non-toxic biodegradable material that decomposes naturally in the body. Nevertheless, Mg has been implicated in problems including diminished physical properties and corrosion resistance when degradation is too rapid prior to bone healing. This study has explored the effect of Ca on the corrosion resistance and biological evaluation after anodizing treatment with different contents of Ca alloy. Binary Mg-0.5Ca, Mg-1Ca and Mg-5Ca alloys were prepared by the casting method under an argon atmosphere and cut into disc-shaped pieces. Pure Mg alloy was used as the control. Anodic oxidation was performed for 15 minutes at a voltage of 120 V using an electrolyte solution containing Ca gluconate, sodium hexametaphosphate, and sodium hydroxide at room temperature. Corrosion resistance was analyzed using a corrosion tester. After a hydrogen evolution test, the surface pattern and phase changes were observed on a scanning electron microscop (SEM) and energy dispersive spectroscop (EDS). Microscopic evaluation of the adhesion and cell biological functions of Mg was conducted by observing the response of human fetal osteoblastic 1.19 cells with regard to changes in surface film properties, depending on the amount of Ca. Our results support the view that in Mg-xCa alloys (x=0.5, 1, 5 wt.%) treated using anodic oxidation, the increasing Ca content controls the rate of decomposition and improves corrosion resistance.
    Źródło:
    Acta Physica Polonica A; 2016, 129, 4; 728-735
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A Study On The Metal Carbide Composite Diffusion Bonding For Mechanical Seal
    Badanie łączenia dyfuzyjnego kompozytu metal węglik na mechaniczne uszczelnienie
    Autorzy:
    Kim, D.-K.
    Shon, I.-J.
    Song, J.
    Ryu, W.-J.
    Shin, H.-Ch.
    Kwon, E.-Y.
    Shin, H.
    Kang, S.-J.
    Powiązania:
    https://bibliotekanauki.pl/articles/356399.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    diffusion bonding
    nanostructures
    mechanical seal
    hard metal
    mechanical properties
    łączenie
    nanostruktura
    uszczelnienie mechaniczne
    twardy metal
    właściwości mechaniczne
    Opis:
    Mechanical Seal use highly efficient alternative water having a great quantity of an aqueous solution and has an advantage no corrosion brine. Metal Carbide composites have been investigated as potential materials for high temperature structural applications and for application in the processing industry. The existing Mechanical seal material is a highly expensive carbide alloy, and it is difficult to take a price advantage. Therefore the study of replacing body area with inexpensive steel material excluding O-ring and contact area which demands high characteristics is needed. The development of WC-Ni base carbide alloy optimal bonding composition technique was accomplished in this study. To check out the influence of bonding temperature and time, bonding characteristics of sintering temperature was experimented. The bonding statuses of this test specimen were excellent. The hardness of specimen and bonding rate were measured using ultrasound equipment. In this work, Powder of WC (involved VC, Cr), Co and Mo2C mixed by attrition milling for 24hours. Nanostructured WC-27.6wt.%Ni-1.5wt.%Si-0.11wt.%VC-1.1wt.%B4C composite were fabricated at 1190°C by high temperature vacuum furnace. To check out the influence of bonding temperature and time, bonding characteristics of sintering temperature was experimented. Its relative density was about 99.7%. The mechanical properties (hardness and fracture toughness) were 87.2 HRA and 4.2 M·Pam1/2, respectively. The bonding status of this test specimen was excellent and the thickness of bonding layer was 20 ~30§ at 1050 and 1060°C bonding temperature.
    Źródło:
    Archives of Metallurgy and Materials; 2015, 60, 2B; 1479-1483
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Low-velocity impact characteristics of composite plates with shape memory alloy wires
    Niskoprędkościowe charakterystyki uderzeniowe płyt kompozytowych zawierających włókna ze stopów z pamięcią kształtu
    Autorzy:
    Rim, M.-S.
    Kim, E.-H.
    Lee, I.
    Choi, I.-H.
    Ahn, S.-M.
    Koo, K.-N.
    Bae, J.-S.
    Roh, J.-H.
    Powiązania:
    https://bibliotekanauki.pl/articles/279293.pdf
    Data publikacji:
    2011
    Wydawca:
    Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
    Tematy:
    shape memory alloy
    SMAHC
    composite
    low-velocity impact
    impact resistance
    Opis:
    To investigate impact characteristics of shape memory alloy hybrid com- posites (SMAHC), several experiments were performed. Tensile tests of shape memory alloy (SMA) wires were carried out to investigate thermomechanical properties, and low-velocity impact tests of SMAHC plates and conventional composite plates without SMAs at the critical energy level. low-velocity impact tests of several types of composite plates, including composite plates with embedded SMAs/Fe/Al wires and conventional composite plates, were also done. Results of these experiments show that embedding SMAs in a composite plate can improve the impact resistance. Lastly, low-velocity impact tests of SMAHC plates with SMA wires embedded at different positions through the thickness were performed in an effort to improve the impact resistance. Embedding SMA wires at a lower position in the composite plates was the most effective for improving the impact resistance.
    Do analizy charakterystyk uderzeniowych hybrydowych kompozytów SMAHC zwierających włókna SMA ze stopów wykazujących efekt pamięci kształtu przeprowadzono szereg badań eksperymentalnych. Przeprowadzono próby na rozciąganie włókien SMA w celu zbadania ich właściwości termomechanicznych oraz niskoprędkościowe testy uderzeniowe płyt SMAHC oraz konwencjonalnych płyt laminowanych przy energii krytycznej. Wykonano także testy dla płyt kompozytowych zawierających włókna SMA/Fe/Al. Rezultaty doświadczeń pokazały, że wbudowanie w strukturę laminatu włókien SMA może zwiększyć odporność kompozytu na obciążenie uderzeniowe. Opisano również badania eksperymentalne płyt SMAHC z włóknami SMA wbudowanymi na różnej głębokości. Wykazano, że najlepsze parametry posiadają kompozyty z włóknami umieszczonymi możliwie daleko od uderzanej powierzchni.
    Źródło:
    Journal of Theoretical and Applied Mechanics; 2011, 49, 3; 841-857
    1429-2955
    Pojawia się w:
    Journal of Theoretical and Applied Mechanics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Multistep Heat-Treatment Effects on Electrospun Nd-Fe-B-O Nanofibers
    Autorzy:
    Jeon, E. J.
    Eom, N. S. A.
    Lee, J.
    Lee, B.
    Cho, H. M.
    On, J. S.
    Choa, Y.-H
    Kim, B. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/354311.pdf
    Data publikacji:
    2018
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Nd-Fe-B
    nanofibers
    electrospinning
    heat treatment
    Opis:
    Neodymium-Iron-Boron (Nd-Fe-B) magnets are considered to have the highest energy density, and their applications include electric motors, generators, hard disc drives, and MRI. It is well known that a fiber structure with a high aspect ratio and the large specific surface area has the potential to overcome the limitations, such as inhomogeneous structures and the difficulty in alignment of easy axis, associated with such magnets obtained by conventional methods. I n this work, a suitable heat-treatment procedure based on single-step and multistep treatments to synthesize sound electrospun Nd-Fe-B-O nanofibers of Φ572 nm was investigated. The single-step heat-treated (directly heat-treated at 800°C for 2 h in air) samples disintegrated along with the residual organic compounds, whereas the multistep heat-treated (sequential three-step heat-treated including three steps;: dehydration (250°C for 30 min in an inert atmosphere), debinding (650°C for 30 min in air), and calcination (800°C for 1 h in air)) fibers maintained sound fibrous morphology without any organic impurities. They could maintain such fibrous morphologies during the dehydration and debinding steps because of the relatively low internal pressures of water vapor and polymer, respectively. In addition, the NdFeO3 alloying phase was dominant in the multistep heat-treated fibers due to the removal of barriers to mass transfer in the interparticles.
    Źródło:
    Archives of Metallurgy and Materials; 2018, 63, 3; 1433-1437
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication of a Spherical Titanium Powder by Combined Combustion Synthesis and DC Plasma Treatment
    Autorzy:
    Choi, S. H.
    Ali, B.
    Hyun, S. K.
    Sim, J. J.
    Choi, W. J.
    Joo, W.
    Lim, J. H.
    Lee, Y. J.
    Kim, T. S.
    Park, K. T.
    Powiązania:
    https://bibliotekanauki.pl/articles/356067.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    combustion synthesis
    DC plasma treatment
    titanium powder
    3D printing process
    combustion parameters
    Opis:
    Combustion synthesis is capable of producing many types of refractory and ceramic materials, as well as metals, with a relatively lower cost and shorter time frame than other solid state synthetic techniques. TiO2 with Mg as reductant were dry mixed and hand compacted into a 60 mm diameter mold and then combusted under an Ar atmosphere. Depending on the reaction parameters (Mg concentration 2 ≤ α ≤ 4), the thermocouples registered temperatures between 1160°C and 1710°C . 3 mol of Mg gave the optimum results with combustion temperature (Tc) and combustion velocity (Uc) values of 1372°C and 0.26 cm/s respectively. Furthermore, this ratio also had the lowest oxygen concentration in this study (0.8 wt%). After combustion, DC plasma treatment was carried out to spheroidize the Ti powder for use in 3D printing. The characterization of the final product was performed using X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, and N/O analysis.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1057-1062
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Development of Ship Watch Keeping Supporting Aids
    Autorzy:
    Im, N.
    Kim, E. K.
    Han, S. H.
    Jeong, J. S.
    Lee, S. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/117602.pdf
    Data publikacji:
    2013
    Wydawca:
    Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
    Tematy:
    Ship Watchkeeping
    Deck Officers
    Navigation Visual Supporting System
    Intelligent Technology
    Dangerous Floating Objects
    Binocular Telescope
    laser distance measuring unit
    Sea Trial Test
    Opis:
    This study deals with the development of ship watch keeping supporting aids that will be useful for ship deck officers in recognizing navigational harmful obstacles such as sea marks and small floating objects on the sea. The developed watch keeping supporting aids is made up of four components; a composite video sensor to produce video signal, a laser distance measuring part, a Pan/Tilt part and a central control part. The system was installed in a ship in order to verify its performance of the recognition ability on the sea. The comparison was made between the recognition ability of the system and that of watch keeping deck officers’. The image from the watch keeping supporting system was found to be more recognizable than that of a binocular telescope within a 5 km distance. The newly suggested system is expected to be used to recognize small dangerous floating objects more easily when navigation deck officers have a duty of watch keeping for navigation especially near harbor area.
    Źródło:
    TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2013, 7, 4; 501-506
    2083-6473
    2083-6481
    Pojawia się w:
    TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Reaction Kinetics and Morphological Study of TiNb2O7 Synthesized by Solid-State Reaction
    Autorzy:
    Choi, S. H.
    Ali, B.
    Choi, K. S.
    Hyun, S. K.
    Sim, J. J.
    Choi, W. J.
    Joo, W.
    Lim, J. H.
    Lee, T. H.
    Kim, T. S.
    Park, K. T.
    Powiązania:
    https://bibliotekanauki.pl/articles/355326.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    solid state reaction
    kinetic analysis
    quantitative phase analysis
    TiNb2O7 synthesis
    Opis:
    Although TiNb2O7 is regarded as a material with high application potential in lithium-ion batteries (LIBs) and solid-oxide fuel cells (SOFCs), it has been difficult to find suitable cost-effective conditions for synthesizing it on a commercial scale. In this study, TiNb2O7 compounds were synthesized by a solid state synthesis process. For stoichiometrically precise synthesis of the TiNb2O7 phase, the starting materials, TiO2 and Nb2O5 were taken in a 1:1 molar ratio. Activation energy and reaction kinetics of the system were investigated at various synthesis temperatures (800,1000,1200, and 1400°C) and for various holding durations (1,5,10, and 20 h). Furthermore, change in the product morphology and particle size distribution were also evaluated as a function of synthesis temperature and duration. Additionally, quantitative phase analysis was conducted using the Rietveld refinement method. It was found that increases in the synthesis temperature and holding time lead to increase in the mean particle size from 1 to 4.5 μm. The reaction rate constant for the synthesis reaction was also calculated.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1051-1056
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Simulation of climate change impacts on grain sorghum production grown under free air CO2 enrichment
    Autorzy:
    Fu, T.
    Ko, J.
    Wall, G.W.
    Pinter,Jr., P.J.
    Kimball, B.A.
    Ottman, M.J.
    Kim, H.-Y.
    Powiązania:
    https://bibliotekanauki.pl/articles/26201.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Instytut Agrofizyki PAN
    Tematy:
    crop simulation
    climate change
    grain yield
    sorghum
    Sorghum bicolor
    productivity
    plant production
    carbon dioxide
    Źródło:
    International Agrophysics; 2016, 30, 3
    0236-8722
    Pojawia się w:
    International Agrophysics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comparison of body surface area-based and weight-based dosing format for oral prednisolone administration in small and large-breed dogs
    Autorzy:
    Nam, A.
    Kim, S.M.
    Jeong, J.W.
    Song, K.H.
    Koo, T.S.
    Seo, K.W.
    Powiązania:
    https://bibliotekanauki.pl/articles/2087897.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Źródło:
    Polish Journal of Veterinary Sciences; 2017, 3; 611-613
    1505-1773
    Pojawia się w:
    Polish Journal of Veterinary Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Carbon Co-Deposition During Gas Reduction of Water-Atomized Fe-Cr-Mo Powder
    Autorzy:
    Ali, B.
    Choi, S. H.
    Seo, S. J.
    Maeng, D. Y.
    Lee, C. G.
    Kim, T. S.
    Park, K. T.
    Powiązania:
    https://bibliotekanauki.pl/articles/352709.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    water atomization
    Fe-based powder
    oxide reduction
    powder metallurgy
    sinter-hardening alloys
    Opis:
    The water atomization of iron powder with a composition of Fe-3Cr-0.5Mo (wt.%) at 1600°C and 150 bar creates an oxide layer, which in this study was reduced using a mixture of methane (CH4) and argon (Ar) gas. The lowest oxygen content was achieved with a 100 cc/min flow rate of CH4, but this also resulted in a co-deposition of carbon due to the cracking of CH4. This carbon can be used directly to create high-quality, sinter hardenable steel, thereby eliminating the need for an additional mixing step prior to sintering. An exponential relationship was found to exist between the CH4 gas flow rate and carbon content of the powder, meaning that its composition can be easily controlled to suit a variety of different applications.
    Źródło:
    Archives of Metallurgy and Materials; 2017, 62, 2B; 1119-1124
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-97 z 97

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