Journal of Korea Foundry Society (한국주조공학회지)

Korea Foundry Society (한국주조공학회)
권호 표지

Microstructures and Mechanical Properties of Diecast 0.7wt% CaO added Eco-Mg Parts

0.7wt% CaO 첨가 AZ91D Eco-Mg 다이캐스팅 부품의 미세조직 및 기계적 특성

  • Seo, Jung-Ho (Foundry Tech. Ctr., Korea Institute of Industrial Technology) ;
  • Lim, Hyun-Kyu (Foundry Tech. Ctr., Korea Institute of Industrial Technology) ;
  • Kim, Shae-K. (Foundry Tech. Ctr., Korea Institute of Industrial Technology)
  • Received : 2010.10.30
  • Accepted : 2010.11.28
  • Published : 2010.12.31
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Abstract

To prevent oxidation of Mg melt, $SF_6$ gas has been generally used for Mg alloys during melting and casting as a cover gas. The use of $SF_6$ gas, however, will be restricted owing to its crucial impact on global warming. Non-$SF_6$ process during melting and casting in diecasting industry has been proved with Eco-Mg alloys by a simple addition of small amount of CaO into Mg alloys. This paper shows non-$SF_6$ diecasting procedures for 0.7wt% CaO added AZ91D Eco-Mg alloys. Cold-chamber diecasting was performed under $CO_2$ atmosphere without $SF_6$ gas. An increment of mechanical properties, especially strength and ductility of Eco-Mg alloys is, in part, due to high-quality melt, refined grain size and $Al_2Ca$ second phase strengthening. Microstructures and mechanical properties of 0.7wt% CaO added AZ91D Eco-Mg alloys are evaluated in comparison with those of conventional AZ91D Mg alloy.

Keywords

References

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