Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "Ha, Seong-Ho" wg kryterium: Autor

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-6 z 6
    Tytuł:
    Effects of SPD by Biaxial Alternate Forging on the Tensile Properties and Microstructure of AZ31B Magnesium Alloy
    Autorzy:
    Shin, Young-Chul
    Ha, Seong-Ho
    Shah, Abdul Wahid
    Powiązania:
    https://bibliotekanauki.pl/articles/2203714.pdf
    Data publikacji:
    2023
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    forging
    magnesium alloy
    grain refinement
    severe plastic deformation
    tensile properties
    Opis:
    The forming limit of AZ31 alloy, a representative Mg-Al-Zn-based wrought alloy, and the effect of severe plastic deformation (SPD) by examining the microstructure change caused by dynamic recrystallization led by high temperature and high dislocation density at 300℃ using a biaxial alternate forging (BAF) were investigated in this study. As a result of BAF test for AZ31 Mg alloy, significant cracks on the ends of workpieces occurred after 7 passes. The microstructure of as-extruded specimen showed the non-uniform distribution of the relatively coarse grains and the fine grains considered to be sub-grains. However, as the number of passes increases, the area of coarse grains gradually disappeared and the fine grains became more dominant in the microstructures. The result of tensile test for workpieces with each forging pass showed an increase in strength depending on pass number was shown with a slight increase of elongation. The Electron Backscatter Diffraction (EBSD) results exhibited that, the microstructure showed the presence of coarse grains and twins after only 1 pass, while the grains appeared to be significantly refined and uniformly distributed after 3 pass, at which the strength and elongation began to increase, simultaneously.
    Źródło:
    Archives of Metallurgy and Materials; 2023, 68, 1; 97--101
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Characterization of Ca Precipitation in Al-Mg Alloys Containing a Trace of Ca During Homogenization
    Autorzy:
    Ha, Seong-Ho
    Shin, Young-Chul
    Kim, Bong-Hwan
    Yoon, Young-Ok
    Lim, Hyun-Kyu
    Lim, Sung-Hwan
    Kim, Shae K.
    Powiązania:
    https://bibliotekanauki.pl/articles/2049165.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Al-Mg system
    precipitation
    Mg+Al2Ca mater alloy
    transmission electron microscope
    phase diagram
    Opis:
    In this study, precipitation of Ca in Al-Mg alloys containing a trace of Ca during homogenization was investigated using a transmission electron microscope (TEM) and calculated phase diagrams. TEM result indicated that the Ca-based particles found in the examined sample are Ca7Mg7.5Si14. From the calculation of Scheil-Gulliver cooling, it was found that the Ca was formed as Al4Ca and C36 laves phases with Mg2Si and Al13Fe4 from other impurities phase during solidification. No Ca-Mg-Si ternary phase existed at the homogenization temperature in the calculated phase diagram. From the phase diagram of Al-Al4Ca-Mg2Si three-phase isothermal at 490°C, it was shown that Ca7Mg6Si14 phase co-exists with Al, Mg2Si and Al4Ca in the largest region and with only Al and Mg2Si in Al4Ca-poor regions. It was thought that the Ca7Mg6Si14 ternary phase was formed by the interaction between Mg2Si and Al4Ca considering that the segregation can occur throughout the entire microstructures.
    Źródło:
    Archives of Metallurgy and Materials; 2021, 66, 4; 959-962
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of Cu Addition on Oxide Growth of Al-7 mass%Mg Alloy at High Temperature
    Autorzy:
    Ha, Seong-Ho
    Shah, Abdul Wahid
    Kim, Bong-Hwan
    Yoon, Young-Ok
    Lim, Hyun-Kyu
    Kim, Shae K.
    Powiązania:
    https://bibliotekanauki.pl/articles/2049221.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Al-Mg system
    Cu addition
    oxidation
    phase diagram
    Opis:
    Effect of Cu addition on oxide growth of Al-7 mass%Mg alloy at high temperature was investigated. As-cast microstructures of Al-7 mass%Mg and Al-7 mass%Mg-1 mass%Cu alloys showed α-Al dendrites and area of secondary particles. The 1 mass%Cu addition into Al-7 mass%Mg alloy formed Mg32(Al, Cu)49 ternary phase with β-Al3Mg2. The total fraction of two Mg-containing phases in Cu-added alloy was higher than the β-Al3Mg2 fraction in Cu-free alloy. From measured weight gains depending on time at 500°C under an air atmosphere, it was shown that all samples exhibited significant weight gains depending on time. Al-7mass%Mg1mass%Cu alloy showed the relatively increased oxidation rate when compared with Cu-free alloy. All the oxidized cross-sections throughout the entire oxidation time showed coarse and dark areas regarded as oxides grown from the surface to inside, but bigger oxidized areas were formed in the Al-7mass%Mg-1mass%Cu alloy containing higher fraction of Mg-based phases in the as-cast microstructure. As a result of compositional analysis on the oxide clusters, it was found that the oxide clusters contained Mg-based oxides formed through internal oxidation during a long time exposure to oxidizing environments.
    Źródło:
    Archives of Metallurgy and Materials; 2021, 66, 3; 699-702
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Influence of Si Addition on Oxide Growth of Al-6 mass%Mg Alloy Melts
    Autorzy:
    Yoon, Young-Ok
    Ha, Seong-Ho
    Shah, Abdul Wahid
    Kim, Bong-Hwan
    Lim, Hyun-Kyu
    Kim, Shae K.
    Powiązania:
    https://bibliotekanauki.pl/articles/2049203.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Al-Mg system
    Si addition
    oxidation
    phase diagram
    Opis:
    Influence of Si addition on oxide layer growth of Al-6 mass%Mg alloys in molten state was investigated in this study. After melt holding for 24 h, the melt surface of only Si-free alloy became significantly bumpy, while no considerably oxidized surface was observed even with 1 mass%Si addition. There was no visible change on the appearance of melt surfaces with increasing Si content. As a result of compositional analysis on the melt samples between before and after melt holding, the Si-added alloys nearly maintained their Mg contents even after the melt holding for 24 h. On the other hand, the Mg content in the Si-free alloy showed a great reduction. The bumpy surface on Si-free alloy melt showed a large amount of pores and oxide clusters in its cross-section, while the Si-added alloy had no significantly grown oxide clusters on the surfaces. As a result of compositional analysis on the surfaces, the oxide clusters in Si-free alloy contained a great amount of Mg and oxygen. The oxide layer on the Si-added alloy was divided into Mg-rich and Mg-poor areas and contained certain amounts of Si. Such a mixed oxide layer containing Si would act as a protective layer during the melt holding for a long duration.
    Źródło:
    Archives of Metallurgy and Materials; 2021, 66, 3; 695-698
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Microstructure Formation of Al-5 mass%Mg Alloy Melts by Interaction with Silica
    Autorzy:
    Kim, Sun-Ki
    Ha, Seong-Ho
    Kim, Bong-Hwan
    Yoon, Young-Ok
    Lim, Hyun-Kyu
    Kim, Shae K.
    Kim, Yong-Jig
    Powiązania:
    https://bibliotekanauki.pl/articles/2049152.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Al-Mg system
    silica
    reduction
    Mg2Si
    phase diagram
    Opis:
    Dissolution of Si in Al-5 mass%Mg alloy melt by the reduction of SiO2 and its effect on microstructure formation of the alloy after solidification were investigated. Al-5 mass%Mg alloy without silica powder had approximately 0.05 mass%Si as an impurity. No significant difference in Si content was observed after the reaction with silica for 10 min, while the Si content increased up to about 0.12 mass% after 30 min. From the microstructure analysis and calculation of Scheil-Gulliver cooling, it was considered that as-cast microstructures of Al-5 mass%Mg-1 mass% SiO2 alloys had the distribution of eutectic phase particles, which are comprised of β-Al3Mg2 and Mg2Si phases. Based on the phase diagrams, only limited amount of Mg can be selectively removed by silica depending on the ratio of Si and Mg. Addition of silica of more than approximately 1.5 mass% in Al-5 mass%Mg alloy led to the formation of spinel and removal of both mg and Al from the melt.
    Źródło:
    Archives of Metallurgy and Materials; 2021, 66, 4; 947-950
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Prediction of High Strain Rate Flow Behavior of 7175 Aluminum Alloy Based on Arrhenius-Type Constitutive Equations
    Autorzy:
    Shin, Young-Chul
    Joung, Dae-Kwan
    Ha, Seong-Ho
    Choi, Ho-Joon
    Hyun, Soong-Keun
    Powiązania:
    https://bibliotekanauki.pl/articles/356627.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    aluminum alloy
    hot compression
    Arrhenius-type equation
    high strain rate flow behavior
    flow stress
    Opis:
    The flow behavior of 7175 aluminum alloy was modeled with Arrhenius-type constitutive equations using flow stress curves during a hot compression test. Compression tests were conducted at three different temperatures (250°C, 350°C, and 450°C) and four different strain rates (0.005, 0.05, 0.5, and 5 s-1). A good consistency between measured and set values in the experimental parameters was shown at strain rates of 0.005, 0.05, and 0.5 s-1, while the measured data at 5 s-1 showed the temperature rise of the specimen, which was attributable to deformation heat generated by the high strain rate, and a fluctuation in the measured strain rates. To minimize errors in the fundamental data and to overcome the limitations of compression tests at high strain rates, constitutive equations were derived using flow curves at 0.005, 0.05, and 0.5 s-1 only. The results indicated that the flow stresses predicted according to the derived constitutive equations were in good agreement with the experimental results not only at strain rates of 0.005, 0.05, and 0.5 s-1 but also at 5 s-1. The prediction of the flow behavior at 5 s-1 was correctly carried out by inputting the constant strain rate and temperature into the constitutive equation.
    Źródło:
    Archives of Metallurgy and Materials; 2020, 65, 4; 1361-1364
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-6 z 6

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies