Fe-13Cr-4Al合金的高温流变行为

Flow Behavior of Fe-13Cr-4Al Alloy at High Temperature

在Gleeble-1500热模拟实验机上对Fe-13Cr-4Al合金进行了等温压缩实验,研究了该材料在变形温度800~1000℃、应变速率0.01~10 s-1条件下的高温流变行为;构建了包含Arrhenius项同时考虑应变、应变速率及温度影响的高温热变形本构方程。结果表明,Fe-13Cr-4Al合金的高温流变应力状态主要受温度和应变速率的影响,并且在较低变形温度和低应变速率(800~900℃、0.01~0.1 s-1)的变形条件下呈现出动态再结晶;而在较高温度(950~1000℃)的变形条件下呈现出动态回复。材料常数Q、α、n和ln A均是应变ε的函数,采用五次多项式可拟合两者之间的关系。同时应用包含应变补偿的本构方程可预测Fe-13Cr-4Al合金在实验温度和应变速率条件下的流变应力。

The high temperature flow stress behaviors of Fe-13Cr-4 Al alloy at high temperature were investigated by isothermal compression test on Gleeble-1500 thermal simulator at 800℃ to 1000 ℃ with strain rate from 0.01 s-1 to 10 s-1. The high temperature hot deformation constitutive equation of Arrhenius-type incorporating the effects of strain, strain rate and temperature was developed. The results show that the deformation temperature and strain rate have a great influence on the flow stress behaviors of Fe-13Cr-4 Al. The dynamic recrystallization occurs at the low temperatures and low strain rates(800-900 ℃, 0.01-0.1 s-1);the dynamic recovery occurs at high temperature(950-1000 ℃). Moreover, the material constants Q, α,n and ln A are calculated as a function of strain ε, and the fifth-order polynomial can be used to fit the relationship between them. The flow stress of Fe-13Cr-4 Al alloy can be predicted by the proposed constitutive equation incorporating strain compensation precisely under the deformation conditions of experiment temperatures and strain rates.