Characteristics of the Unidirectionally Solidified Al-Co Alloy

일방향응고시킨 Al-Co 합금의 특성에 관한 연구

  • Park, Su-Jung (Dept. of Metallugical and material Eng., Chosun University) ;
  • Jun, Hyun-Yong (Dept. of Metallugical and material Eng., Chosun University) ;
  • Lee, Hyun-Kyu (Dept. of Metallugical and material Eng., Chosun University)
  • 박수정 (조선대학교 금속재료공학과) ;
  • 전현용 (조선대학교 금속재료공학과) ;
  • 이현규 (조선대학교 금속재료공학과)
  • Published : 2005.02.20

Abstract

The structures and mechanical property of the unidirectionally solidified Al-Co eutectic alloy were investigated. Al-Co eutectic alloy was unidirectionally solidified with growth rates(R) between I cm/hr and 10 cm/hr in the induction furnace maintaining the thermal gradient (G) at solid-liquid interface, $32^{\circ}C$/cm. The eutectic microstructure was varied with the growth condition(G/R ratio). When the G/R ratio was larger than $8.5{\times}10^{3}^{\circ}C/cm^{2}/sec$, a lamellar structure was formed, But the G/R ratio was smaller than $8.5{\times}10^{3}^{\circ}C/cm^{2}/sec$, a colony structure was formed. It was found that the interlamellar spacing(${\lambda}$) was dependent on the growth rate(R) with the relationship, ${\lambda}^{2}{\cdot}R=constant$. The microhardness of this eutectic alloy increased with increase in the growth rate.

Keywords

References

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