Journal of Korea Foundry Society (한국주조공학회지)

Korea Foundry Society (한국주조공학회)
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Optimum Fabrication Conditions and Reheating Characteristic of Semi-Solid Al-Zn-Mg-(Sc) Alloy by Inclined Cooling Plate

경사냉각판을 이용한 Al-Zn-Mg-(Sc) 반응고 합금 제조의 최적화 및 재가열 특성

  • Kim, Tae-Hun (i-Cube Center, Engineering Research Institute, Gyeongsang National University) ;
  • Shim, Sung-Yong (i-Cube Center, Engineering Research Institute, Gyeongsang National University) ;
  • Park, Hyung-Won (i-Cube Center, Engineering Research Institute, Gyeongsang National University) ;
  • Lim, Su-Gun (i-Cube Center, Engineering Research Institute, Gyeongsang National University)
  • 김태훈 (경상대학교 공학연구원 아이큐브 센터) ;
  • 심성용 (경상대학교 공학연구원 아이큐브 센터) ;
  • 박형원 (경상대학교 공학연구원 아이큐브 센터) ;
  • 임수근 (경상대학교 공학연구원 아이큐브 센터)
  • Published : 2009.10.31
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Abstract

Optimum conditions for production of semi-solid Al-Zn-Mg alloy billets was carried out by the Taguchi design method. And, Al-Zn-Mg alloy billets contained Sc (free, 0.1 and 0.3 mass %) were fabricated at optimum conditions. Evolution of microstructure in semi-solid state was investigated through various liquid fractions, holding times and holding temperatures. The Al-Zn-Mg alloy billets reheated at $615^{\circ}C$ during 30min are grain growth and it was fractured due to increasing liquid fraction before quenching. And, during reheating up to $600^{\circ}C$, grain growth of Al-Zn-Mg alloy billets contained Sc (0.1 and 0.3 mass %) was not occurred in comparison with those of Al-Zn-Mg alloy without Sc. It was thought that $Al_3Sc$ phases have a pinning effect in grain boundary and Sc content of 0.1 mass% is able to inhibit grain growth effectively through reheating process.

Keywords

References

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