pISSN : 1598-706X / eISSN : 2288-8381
한국주조공학회지 (30권5호 161-166)
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
Sang-Soo Shin*, Myung-Yong Kim**, Gil-Yong Yeom***
*Korea Institute of Industrial Technology, **KOMSCO Co., ***ECO-Diecast Korea Co.
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 μm to less than 0.8 μm. From these results, the optimal strontium content and holding time were identified on the Al- 10.5wt%Si-2wt%Cu secondary die-casting alloy.
Eutectic Si, Modification, Die-casting alloys, Strontium, Fine fibrous, Holding time.