Journal of Korea Foundry Society (한국주조공학회지)

Korea Foundry Society (한국주조공학회)
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The Effect of Sr on the Microstructures of Hypereutectic Al-Si Alloys

과공정 Al-Si 합금의 미세조직에 영향을 미치는 Sr의 영향

  • Kim, Myung-Han (Department of Advanced Materials Engineering, Chungbuk National University)
  • 김명한 (충북대학교 공과대학 신소재공학과)
  • Published : 2006.06.20
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Abstract

Sr, added in the hypereutectic Al-Si alloys, is absorbed on the surfaces of primary Si as well as eutectic Si, and can change the growth mode of primary Si from non-faceted to faceted mode, as the amount of Sr increases larger than 0.04 wt.%, even though it cannot affect the grain size of primary Si, significantly. The EBSD analysis shows that the traction of ${\Sigma}3$ boundary(twin boundary) increases as the amount of Sr in the hypereutectic Al-Si alloys increase until the over-modification occurs at 1.6 wt.%Sr and proves that the change in growth mode of primary Si results from the change of TPRE growth to IIT growth.

Keywords

References

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