Journal of Korea Foundry Society (한국주조공학회지)

Korea Foundry Society (한국주조공학회)
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Influence of Cooling Rate and Alloy Composition on The Microstructural Evolution of Al-Ag Eutectic System

$Al-Ag_2Al$ 공정계 합금의 조성 및 냉각 속도에 따른 미세조직 고찰

  • Sohn, Sung-Woo (Center for Noncrystalline Materials, Department of Metallurgical Engineering, Yonsei University) ;
  • Park, Jin-Man (Center for Noncrystalline Materials, Department of Metallurgical Engineering, Yonsei University, Institute for Complex Materials, IFW-Dresden, Institute for Complex Materials) ;
  • Kim, Tae-Eung (Center for Noncrystalline Materials, Department of Metallurgical Engineering, Yonsei University) ;
  • Lim, Ka-Ram (Center for Noncrystalline Materials, Department of Metallurgical Engineering, Yonsei University) ;
  • Kim, Won-Tae (Division of Applied Science, Cheongju University) ;
  • Kim, Do-Hyang (Center for Noncrystalline Materials, Department of Metallurgical Engineering, Yonsei University)
  • 손성우 (준결정재료 연구단 / 연세대학교 금속시스템공학과) ;
  • 박진만 (준결정재료 연구단 / 연세대학교 금속시스템공학과) ;
  • 김태응 (준결정재료 연구단 / 연세대학교 금속시스템공학과) ;
  • 임가람 (준결정재료 연구단 / 연세대학교 금속시스템공학과) ;
  • 김원태 (청주대학교 응용과학부) ;
  • 김도향 (준결정재료 연구단 / 연세대학교 금속시스템공학과)
  • Published : 2009.06.30
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Abstract

In the present study the effect of cooling rate during solidification on the microstructural characteristics of Al-xAg (x = 31, 33, 35 at.%) in-situ binary eutectic composites has been investigated. To provide a wide range of cooling rate three different casting techniques, i.e. conventional casting, injection casting, and melt spinning have been used. The observed microstructure is very much dependent on the cooling rate. The fcc ${\alpha}$-Al and hcp $Ag_2Al$ phases exhibits an orientation of (111)Al//(0001)$Ag_2Al$, [1-10]Al//[11- 20]$Ag_2Al$. The microstructure of the melt-spun samples contains Widmanstatten structure resulting from solid-state transformation and nano scale two-phase structure resulting from solid-state phase separation. The microstructure of injection-cast samples contains eutectic structure and solid state phase-separated structure. On the other hand, conventional-cast samples exhibit a microstructure consisted of plate-type eutectic structure.

Keywords

References

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