Journal of Korea Foundry Society (한국주조공학회지)

Korea Foundry Society (한국주조공학회)
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The Effect of Sr Addition and Holding Time on Microstructure of Al-10.5%Si-2%Cu Secondary Die-casting Alloys

Al-10.5wt%Si-2wt%Cu 다이 캐스팅용 2차 지금의 미세조직에 미치는 Sr의 양과 유지시간의 영향 I

  • 신상수 (한국생산기술연구원 친환경청정기술센터) ;
  • 김명용 (한국조폐공사) ;
  • 염길용 (에코 다이캐스트 코리아)
  • Received : 2010.08.26
  • Accepted : 2010.09.22
  • Published : 2010.10.31
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Abstract

In this examination, the effect of Sr addition and holding time on microstructure of Al-10.5wt%Si-2wt%Cu secondary die-casting alloy was investigated. Degree of undercooling was improved with increasing the Sr content in this alloy. Up to 0.02wt%Sr addition, acicular and lamellar eutectic structure was observed in the microstructure. Meanwhile, the eutectic Si was modified toward the fine fibrous form by increasing Sr content with more than 0.03wt% and holding time of the melt. The well- modified alloys showed decreased eutectic silicon size from 3.25 ${\mu}m$ to less than 0.8 ${\mu}m$. From these results, the optimal strontium content and holding time were identified on the Al-10.5wt%Si-2wt%Cu secondary die-casting alloy.

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