High Temperature Compressive Deformation Behavior of Ti-6Al-2Sn-4Zr-6Mo Alloy

Ti-6Al-2Sn-4Zr-6Mo 합금의 고온압축 변형거동

  • 현용택 (한국기계연구원 재료공정연구부) ;
  • 이용태 (한국기계연구원 재료공정연구부) ;
  • 이찬규 (창원대학교 금속재료공학과)
  • Published : 2001.02.01

Abstract

The hot deformation behavior of Ti-6Al-2Sn-4Zr-6Mo(Ti6246) alloy was investigated in both the $\alpha$+$\beta$ and $\beta$-phase fields by conducting compression tests over a strain rate range of $10^{-3}s^{-1}$ to $10^0s^{-1}$. The flow stress was increased with increasing strain rate and decreasing test temperature. The flow curves obtained at temperatures below 90$0^{\circ}C$ exhibited a flow softening. However, in the $\beta$-phase field, above 95$0^{\circ}C$, the flow stress increased monotonically with plastic strain approaching steady state values. Constitutive equations for the dependence of flow stress on strain, strain rate, and temperature were developed through the analysis of the flow curves.

Ti-6Al-2Sn-4Zr-6Mo(Ti6246) 합금의 고온 변형거동을 조사하기 위하여 $\alpha$+$\beta$ 영역 및 $\beta$영역의 온도에서 $10^0s^{-1}$에서 $10^{-3}s^{-1}$의 변형속도로 압축시험을 수행하였다. 유동응력은 변형속도가 증가하고 시험 온도가 감소함에 따라 증가하였다 90$0^{\circ}C$ 이하에서 시험한 결과로부터 얻어진 유동곡선은 가공연화 현상을 나타내었으나, 이 합금의$\beta$영역인 95$0^{\circ}C$ 이상에서는 유동응력이 지속적으로 증가하다가 정상 상태를 나타냈다. 압축시험 결과로부터 얻은 유동곡선 분석을 통하여 유동응력의 변형량, 변형속도 및 온도에 대한 관계로부터 이 합금에 대한 구성방정식을 구하였다.

Keywords

References

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