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Tytuł:
Wybrane własności stopowej warstwy wierzchniej na bazie wolframu, wytworzonej techniką ESD
Investigation of the selected properties of superficial layer alloyed with the tungsten electrodes using ESD technique
Autorzy:
Spadło, S.
Młynarczyk, P.
Depczyński, W.
Powiązania:
https://bibliotekanauki.pl/articles/252000.pdf
Data publikacji:
2015
Wydawca:
Instytut Naukowo-Wydawniczy TTS
Tematy:
technika ESD
elektroda wolframowa
elektroda stopowa
ESD technique
tungsten electrode
alloy electrode
Opis:
W pracy przedstawiono krótką analizę mikroosadzania elektroiskrowego z użyciem elektrody wolframowej. Metoda osadzania elektroiskrowego (ESD) jest metodą obróbki wykonywaną na obrabiarkach EDM wykorzystującą także elektrody stopowe. Elektroda jest wykonana z materiału, który ma być osadzony na powierzchni części obrabianej. Zwrócono uwagę na możliwości stosowania hybrydowego stopowania (wyładowania elektrycznego z oddziaływaniem mechanicznym) jako proces doskonalenia powierzchni dla skomplikowanych części maszyn. Powłoki przeciwzużyciowe nałożono na stal węglową C45 z wykorzystaniem mikrowyładowań elektrycznych pomiędzy powierzchnią stopowaną i drutem elektrody. Szczególną uwagę zwrócono na możliwości stosowania metody w zwiększaniu odporności na ścierania narzędzi, form wtryskowych i części maszyn. Dokonano oceny rozkładu pierwiastków w warstwie wierzchniej. Wyniki badań wykazały, że istnieje możliwość uzyskania zadowalającej jakości połączenia pomiędzy stalą C45 i nanoszoną warstwą wolframową.
The paper presents a brief study of microelectrospark deposition (ESD) with use of a tungsten electrode. The electrodischarge alloying with wire electrodes is machining method performed on using EDM machine with the help of alloy electrode. Electrode is made of material which is to be deposited on the part surface. Attention has been paid to the possibilities of applying hybrid alloying (electrical discharge deposition with mechanical interaction) as a surface improvement process for complex shape parts. The antiwear coatings were applied on carbon steel C45 with use of micro electrical discharges between alloy-ing surface and wire electrode. Special attention has been paid to the possibilities of applying mentioned method to increase abrasive wear resistance of tools, injection moulds and machine parts. Evaluation of elements distribution in the superficial layer was made. The results of investigations showed that there is a possibility to obtain the satisfying quality of joint between the carbon steel C45 and tungsten layer.
Źródło:
TTS Technika Transportu Szynowego; 2015, 12; 1411-1413, CD
1232-3829
2543-5728
Pojawia się w:
TTS Technika Transportu Szynowego
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multi-criteria optimization method in micro-EDM using TiN coated tungsten carbide electrode
Autorzy:
Nguyen, Phan-Huu
Powiązania:
https://bibliotekanauki.pl/articles/2086282.pdf
Data publikacji:
2022
Wydawca:
Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
Tematy:
micro-EDM
coated electrode
TOPSIS
Opis:
Even though the coated electrode can enhance the machining efficiency in micro-EDM process, it is essential to introduce optimization approach for further enhancing the process. Hence the present study was performed with multi-criteria optimization in micro-EDM using TiN coated tungsten carbide electrode for machining Ti-6Al-4V. The Z coordinator (Z) and tool wear rate (TWR) were used as the quality parameters to evaluate the machinability. The voltage (U), capacitance (C) and spindle rotational speed (n) were considered a the technological parameters. The Technique for order preference by similarity to ideal solution (TOPSIS) method was a suitable solution to determine the optimal result with the help of S/N analysis and by ranking. It was found that capacitance has more significant nature in the process. The optimal process parameters combination was found with better accuracy and lower prediction error of 1.03%. The better machined surface quality was also observed under optimal conditions.
Źródło:
Journal of Machine Engineering; 2022, 22, 2; 148--160
1895-7595
2391-8071
Pojawia się w:
Journal of Machine Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The optimization of micro-EDM machining process when using carbon coated micro electrode as a tool
Autorzy:
Mac, Thi Bich
Shirguppikar, Shailesh
Ganachari, Vaibhav
Powiązania:
https://bibliotekanauki.pl/articles/24084638.pdf
Data publikacji:
2023
Wydawca:
Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
Tematy:
micro-EDM
coated electrode
optimisation
Opis:
The amount of electrode wear in micro-EDM has a direct effect on the dimensional accuracy of the machined hole. Therefore, improving the corrosion resistance of electrodes in micro-EDM is still of great interest. The effective coating of thin film for the micro tool electrodes in the case of micro-EDM can lead to minimize the electrode wear which eventually improve the productivity and machining quality. In the present study, experiments were performed on micro-EDM using carbon coated tool electrode and optimized using Taguchi-Topsis to investigate optimum levels of Depth of cut (Z) and overcut (OVC). It was concluded that optimum conditions had improved significantly using carbon coated micro tool electrode. Optimal levels of technological parameters include V = 160 V, C = 10000 pF, RPM = 600 rpm, and Zopt = 2.525 mm, OVCopt = 65.257 µm. The quality of the machined surface with the coated electrode at optimal conditions is analysed and evaluated. The Topsis method is a suitable solution to this problem, and the steps to perform the calculation in this technique are simple.
Źródło:
Journal of Machine Engineering; 2023, 23, 2; 186--197
1895-7595
2391-8071
Pojawia się w:
Journal of Machine Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An investigation of the effect of NaCl concentration on the electrocoagulation of coal preparation plant tailings
Autorzy:
Eskibalci, M. F.
Ozkan, M. F.
Powiązania:
https://bibliotekanauki.pl/articles/110279.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
coal
tailing
electrocoagulation
electrode
coagulalion
Opis:
Coal preparation is the process of separating the coal from mineral impurities to produce high-grade coal, and the wastewater of the coal separation process is mainly consisted of fine coal and clay particles. Electrocoagulation (EC) is one of the effective methods for wastewater treatment. In this context, this study was aimed to investigate the evaluation of EC process for coal preparation plant wastewaters. Several key parameters affecting the efficiency of EC were investigated with laboratory scale experiments in search of optimal parameter values. Most importantly, the effect of NaCl concentration on the precipitation of coal preparation plant tailings by EC was investigated. Current density, electrolysis time, mixing speed, mixing time, pH, and salt concentration were studied using an aluminum electrode. Based on the results obtained from this study, the optimum conditions were found to be as pH 7.88 (natural pH), current density 40 (A/m2), mixing speed 360 rpm, premixing time 120 sec, and electrolysis time 300 sec. Under the optimum operating conditions, the results indicated that EC can be successfully applied for the coal preparation wastewaters, and the turbidity was reduced from 1260 NTU to 63 NTU (95% efficiency) with an operating cost of $5.67/Mg of tailings. By the increasing the salt content, a small increase in the turbidity was observed with a decrease in the voltage. With only a 1% decrease in the removal efficiency, the cost was reduced to $3.19/Mg with a 44% operating cost reduction.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 3; 934-943
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sulfide-selective electrodes based on the sulfided monocrystals of CdSb
Autorzy:
Diichuk, V. V
Powiązania:
https://bibliotekanauki.pl/articles/134875.pdf
Data publikacji:
2014
Wydawca:
Tomasz Mariusz Majka
Tematy:
sulfidizing
semiconducting monocrystal
sulfide-sensitive electrode
Opis:
A method of formation of the sulfide-sensitive electrodes in the water-free superbasic solutions using the sulfided semiconducting CdSb monocrystals has been investigated. The effective range of the sulfide ions concentration was found and some other conditions were determined in order to ensure formation of the electrodes with the linear potential/sulfide concentration characteristics. Using the atom absorption spectrometry, the 6:1 molar ratio was found for the Cd and Sb atoms concentrations in the surface electrode film.
Źródło:
Journal of Education and Technical Sciences; 2014, 1, 1; 5-7
2300-7419
2392-036X
Pojawia się w:
Journal of Education and Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Analysis of Filler Material Effect on Properties of Excavator Crawler Track Shoe after Welding Regeneration
Autorzy:
Gucwa, M.
Winczek, J.
Wieczorek, P.
Mičian, M.
Koňár, R.
Powiązania:
https://bibliotekanauki.pl/articles/2049557.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
hardfacing
carbides
hardness
wear
covered electrode
Opis:
The application of hardfacing is one of the ways to restore the functional properties of worn elements. The possibility of using filler materials rich in chrome allows for better wear resistance than base materials used so far. The paper presents the results of research on the use of 3 different grades of covered electrodes for the regeneration of worn track staves. The content of the carbon in the covered electrodes was from 0,5% to 7% and the chromium from 5% to 33%. The microscopic and hardness tests revealed large differences in the structure and properties of the welds. The differences in the hardness of the welds between the materials used were up to 150 HV units. The difference in wear resistance, in the ASTM G65 test, between the best and worst materials was almost 12 times big.
Źródło:
Archives of Metallurgy and Materials; 2021, 66, 1; 31-36
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Role of a biased electrode in the production of highly charged ions using the DECRIS 14-3 ion source
Autorzy:
Leporis, M.
Bogomolov, S.
Efremov, A.
Loginov, V.
Mironov, V.
Powiązania:
https://bibliotekanauki.pl/articles/148672.pdf
Data publikacji:
2003
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
ECR ion source
plasma
biased electrode
Opis:
ECR ion sources are used for the production of highly charged ions in various accelerator facilities. In most of them biased electrodes are normally used to increase the ion yield. Physical processes in the plasma of an ion source are quite complicated and the role of a biased electrode is not clear. To investigate the effect of a biased electrode on the intensity of extracted highly charged ions, an axially movable electrode was placed into the plasma chamber of the DECRIS 14-3 ion source. It was found that the intensity of Ar ions depends on the position of the biased electrode and negative bias voltage. The optimal position of the biased electrode was found near the maximum of the magnetic field. Experiments with a pulsed biased electrode were also carried out. The influence of the negative pulse on the ion yield depends on the ion charge state.
Źródło:
Nukleonika; 2003, 48,suppl.2; 89-92
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on the properties of high chromium cast iron overlay welds deposited by tubular electrodes
Badanie własności warstw napawanych żeliwem chromowym elektrodami otulonymi rurkowymi
Autorzy:
Szymura, M.
Czupryński, A.
Różański, M.
Powiązania:
https://bibliotekanauki.pl/articles/115051.pdf
Data publikacji:
2018
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
napawanie
elektroda rurkowa
elektroda otulona
ścieranie
żeliwo chromowe
hardfacing
tubular electrode
covered electrode
abrasion
chromium cast iron
Opis:
In the paper, there were shown the results of research on the properties of overlay welds consisted of one and three layers deposited by three types of tubular electrodes of the Fe-Cr-C alloy, Fe-Cr-C-Nb-Mo-W-V alloy and composite consist of tungsten carbide particles in the Fe-Cr-C alloy matrix. The study of hardfacing deposits included: test of metal-mineral abrasion resistance, metallographic examinations, analysis of chemical composition, and hardness tests. The test of abrasive usage in metal-mineral friction was made according to the procedure A of the ASTM G 65 standard.
W artykule przedstawiono wyniki badania własności napoin jedno- i trójwarstwowych wykonanych trzema rodzajami elektrod rurkowych ze stopów Fe-Cr-C, Fe-Cr-C-Nb-Mo-W-V oraz kompozytu składającego się z cząstek węglika wolframu w osnowie ze stopu Fe-Cr-C. Badania napoin obejmowały: badania odporności na zużycie ścierne typu metal-minerał, badania metalograficzne, analizę składu chemicznego oraz pomiar twardości. Badanie odporności na zużycie ścierne typu metal-minerał przeprowadzono zgodnie z normą ASTM G 65, procedura A.
Źródło:
Welding Technology Review; 2018, 90, 10; 26-30
0033-2364
2449-7959
Pojawia się w:
Welding Technology Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparison of the properties of lignins as potential carbon precursors
Autorzy:
Mielan, Bartosz
Musioł, Patrycja
Tomala, Janusz
Błażewicz, Stanisław
Frączek-Szczypta, Aneta
Powiązania:
https://bibliotekanauki.pl/articles/2010830.pdf
Data publikacji:
2020
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Technologii Drewna
Tematy:
lignin
carbonization
carbon electrode
graphitization
renewable resources
Opis:
Due to growing interest in the application of renewable resources in industry, there is a need for new carbon precursors. Lignin is a natural polymer and the main by-product of the paper industry, but its application on an industrial scale is limited. Due to its chemical composition and high aromatic carbon content, combined with a lack of toxicity, it may be a promising candidate for a carbon precursor, as well as – in carbon electrode technology – a carbon binder. The main disadvantage of lignins is the variety of their types, with differing properties. There is a need to establish the relationship between the structure of lignin and its carbon precursor potential. In this work, an attempt was made to find the dependence between the lignin structure and its properties before (chemical composition, structural studies) and after thermal treatment under an inert atmosphere (carbon residue, bonding properties and degree of carbonization and graphitization), using different techniques (FTIR, Raman spectroscopy, XPS, TG, SEM) on two softwood lignins – alkali lignin and kraft lignin. The results proved that both lignins are good candidates for carbon precursors (high mass residue after heat treatment), but only kraft lignin exhibits the bonding properties which are crucial for application as a carbon binder.
Źródło:
Drewno. Prace Naukowe. Doniesienia. Komunikaty; 2020, 63, 206; 19-34
1644-3985
Pojawia się w:
Drewno. Prace Naukowe. Doniesienia. Komunikaty
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research of electrolyte low loss in typical ECM gaps
Autorzy:
Paczkowski, T.
Zdrojewski, J.
Bujnowski, S.
Janicki, D.
Powiązania:
https://bibliotekanauki.pl/articles/99886.pdf
Data publikacji:
2012
Wydawca:
Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
Tematy:
ECM
electrolyte flow loss
curvilinear electrode surfaces
Opis:
This paper presents the results of research of hydraulic loss during electrolyte flow through gaps typical for ECM machining. The research was conducted on a test station where inducing an oscillatory movement of electrodes was possible. Appropriately prepared electrodes with curvilinear outlines were placed in a machining unit which allowed for measuring the pressure of the electrolyte flow in eight points on the electrode surface and also interelectrode gap inlet and outlet. Additionally, the results of pressure measurements were compared with results obtained from a computer simulation.
Źródło:
Journal of Machine Engineering; 2012, 12, 2; 86-91
1895-7595
2391-8071
Pojawia się w:
Journal of Machine Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Treatment of Surface Treatment Effluents by Electrocoagulation Process Using Aluminium Electrodes
Autorzy:
Namoussi, Soukaina
Merbouh, Chaimaa
Kabriti, Mohamed
Nahli, Abdelmottalib
Naamane, Ayoub
Chlaida, Mohamed
Iounes, Nadia
Powiązania:
https://bibliotekanauki.pl/articles/2025816.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
electrocoagulation
aluminium electrode
surface treatment
effluent
pollutant
Opis:
The surface treatment industry generates effluents with a high load of highly toxic chemicals which must be treated under increasingly stringent regulation. The aim of this study was to treat the effluents of surface treatment unit of an aeronautical industry by the electrocoagulation process using aluminium electrodes. This process is used to study the performance to remove colloidal load, significant amount of oxidizable material and high levels of various metal elements (Cr, Fe, Zn, Cu and Al) from these effluents, under optimum conditions of pH 7, 8.6A of current intensity and 60 min of application. The electrocoagulation process was found to be effective in reducing turbidity (97.12%), COD (97.5%), SS (97.84%) and conductivity (96.82%), hexavalent chromium (99.99%), Zn (96.82%), Cu (94.3%), Iron (99.9%), Al (91.96%). The treated effluent conformed to the Moroccan standards of surface treatment discharge.
Źródło:
Journal of Ecological Engineering; 2022, 23, 1; 91-99
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Procedure for correction of the ECG signal error introduced by skin-electrode interface
Autorzy:
Tomczyk, K.
Powiązania:
https://bibliotekanauki.pl/articles/221734.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
identification of skin-electrode interface
signals reconstruction
Opis:
The paper presents a procedure for correction of the error of an ECG signal, introduced by the skin-electrode interface. This procedure involves three main measuring-calculating stages: parametrical identification of the mathematical model of the interface, realized directly before the diagnostic measurements, registration of the signal at the output of electrodes as well as reconstruction of the input signal of the interface. The first two stages are realized in the on-line mode, whereas the operation of signal reconstruction presents a numerical task of digital signal processing and is realized in the off-line mode through deconvolution of the registered signal with the transfer function of the skin-electrode interface. The aim of the paper is to discuss in detail the procedure of parametric identification of the skin-electrode interface with the use of a computer system equipped with a DAQ card and LabVIEW software. The algorithm for error correction introduced by this interface is also presented.
Źródło:
Metrology and Measurement Systems; 2011, 18, 3; 461-470
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of Plasma Actuator with Two Mesh Electrodes to Active Control of Boundary Layer at 50 Hz Power Supply
Autorzy:
Gnapowski, Ernest
Pytka, Jarosław
Gnapowski, Sebastian
Józwik, Jerzy
Tomiło, Paweł
Powiązania:
https://bibliotekanauki.pl/articles/2201893.pdf
Data publikacji:
2023
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
plasma actuator
DBD
lift coefficient
mesh electrode
Opis:
Numerous studies are conducted to improve the flow in the boundary layer to ensure laminar flow and in particular to increase flight safety. A new solution used to improve the laminar flow is the plasma actuator. The classic configuration of DBD plasma actuators is commonly used with the asymmetric electrode system. The manuscript describes the results of tests with a plasma actuator. Experimental tests were carried out on the built model of the wing with the SD 7003 profile, a plasma actuator was mounted on the upper surface. In contrast to the commonly used solution with solid tape copper electrodes, the novelty in the described research in the manuscript is the use of a large GND electrode (covering 70% of the upper surface of the wing) and a HV mesh electrode. The use of a plasma actuator on the upper surface of the wing affects the air flow in the boundary layer as a result of air ionization. The tests were carried out for a supply voltage from V = 7.0 kV to 12 kV and Reynolds number, Re = 87500 to 240000, flow velocity during the tests in the tunnel was in the range of U = 5-15 m/s and the angle of attack α = 5 -15 degrees. On the basis of the results experimental tests, the percentage change in the lift coefficient was calculated for the switched on and off DBD system. The obtained results indicate a maximum 17% increase in the lift coefficient for the plasma actuator activated for air flow U = 5 m/s and angle of attack α = 5 degrees. In the remaining configurations, changes in the lift coefficient amounted to 4%.
Źródło:
Advances in Science and Technology. Research Journal; 2023, 17, 1; 58--63
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modified solid ion-selective electrode for potentiometric determination of sulfide in oil refineries water
Autorzy:
Abdullad, Zeyad K.
Al-Samarrai, Shatha Y.
Powiązania:
https://bibliotekanauki.pl/articles/35520351.pdf
Data publikacji:
2021
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
ion-selective electrode
silver sulfide
oil refineries
water
Opis:
A selective electrode was manufactured to determine the sulfur ions by sedimentation method in industrial waters in oil refineries of North Refineries Company, Baiji, Iraq. The linear response on a wide range of concentration (from 1.0·10–1 to 1.0·10–6M) Na2S with a Nernst response of 28.229 mv per decade, theoretical value for slope of 29.58 mv per decade, correlation factor of 0.9998, detection limit of 2.287·10–7 at 25–35°C, pH 6.0–12.0, and the best concentration of the filling solution of 10–6M with a fast response time (5–13 s). The direct method were %RSD for 0.5772– –0.7430, %RE for –0.1, 3.7 and %REC for 99.9, 103.7.
Źródło:
Scientific Review Engineering and Environmental Sciences; 2021, 30, 1; 98-105
1732-9353
Pojawia się w:
Scientific Review Engineering and Environmental Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The research methodology of powders with particle size of under 500 microns
Autorzy:
Żegleń, K.
Grygier, D.
Ambroziak, A.
Żak, A.
Powiązania:
https://bibliotekanauki.pl/articles/1190004.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
metodologia
druty proszkowe
proszki
methodology
tubular electrode
powders
Opis:
Wyniki przedstawione w artykule są zobrazowaniem metodologii będącej tematem tej pracy. Zawiera ona opis głównych metod badań jak obserwacje mikroskopowe, analiza sitowa oraz określanie składu chemicznego z wykorzystaniem detektora EDX. Wyniki przedstawiają określenie kształtu cząstek, określenie wielkości cząstek wraz z wyróżnieniem frakcji o największym udziale procentowym oraz określenie składu chemicznego. Celem artykułu jest przedstawienie kolejności wykonywania badań dotyczących proszku żelaza o granulacji do 250 mikrometrów. Badania te można również z powodzeniem zastosować do określania wymienionych wielkości proszków o granulacji do 500 mikrometrów.
Źródło:
Interdisciplinary Journal of Engineering Sciences; 2016, 4, 1; 15--18
2300-5874
Pojawia się w:
Interdisciplinary Journal of Engineering Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł

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