Journal of Korea Foundry Society (한국주조공학회지)

Korea Foundry Society (한국주조공학회)
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Microstructural evolution and mechanical properties of $Al_{71.6}Ge_{28.4}$ eutectic alloy

$Al_{71.6}Ge_{28.4}$ 공정합금의 미세구조 및 기계적 성질의 평가

  • Park, Jin-Man (Center for Non-crystalline Materials/Dept. of Metallurgical Eng., Yonsei University) ;
  • Yook, Wan (Center for Non-crystalline Materials/Dept. of Metallurgical Eng., Yonsei University) ;
  • Kim, Do-Hyang (Center for Non-crystalline Materials/Dept. of Metallurgical Eng., Yonsei University)
  • 박진만 (준결정재료연구단/연세대학교 금속시스템공학과) ;
  • 육완 (준결정재료연구단/연세대학교 금속시스템공학과) ;
  • 김도향 (준결정재료연구단/연세대학교 금속시스템공학과)
  • Published : 2007.07.20
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Abstract

In the present study, the microstructural evolution and mechanical properties of $Al_{71.6}Ge_{28.4}$ eutectic alloy have been investigated. Stable (fcc ${\alpha}$-Al and diamond cubic ${\beta}$-Ge) and various metastable crystalline (monoclinic, rhombohedral) phases were produced by competitive phase selection during non-equilibrium processing methods i.e. melt spinning and injection casting. The as-injection casted samples containing metastable-equilibrium eutectic (${\alpha}$-Al + monoclinic) structure showed much higher strength than samples with equilibrium eutectic (${\alpha}-Al+{\beta}-Ge$) structure but plasticity disappointingly diminished. In order to endow the enhanced ductility without significant strength drop, the alloys was heat-treated at transition temperature from metastable phase to stable phase. The annealed specimen displayed the phase transformed microstructural evolution and enhanced macroscopic plasticity.

Keywords

References

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