TC31钛合金板材高温流变行为及组织演变研究

Research on High Temperature Flow Behavior and Microstructure Evolution of TC31 Titanium Alloy Sheets

摘要:

本文研究了TC31钛合金在840~960℃ 0.0001~0.1s_^-1条件下的高温流变行为,分析了变形温度、应变速率、应变量对其流变应力和微观组织的影响。结合Z参数,建立了TC31钛合金的Arrhenius本构方程。结果表明,当温度低于880℃,应变速率高于0.01s_^-1,材料出现了明显的动态软化现象；当温度高于920℃,应变速率低于0.001s_^-1时,晶粒粗大导致宏观流变应力增长；应变量、应变速率和变形温度对晶粒尺寸、形状和相含量都有不同程度的影响。此外,本文还证实基于应变修正的Arrhenius本构方程拥有较高的预测精度,经计算得其MSE为2.443,R值为0.9675。

Abstract:

The high temperature flow behavior of TC31 titanium alloy at the 840~960℃ 0.0001~0.1s_^-1. and the effects of the deformation temperature, strain rate and strain on flow stress and microstructure were studied, respectively. the Arrhenius constitutive equation of TC31 titanium alloy was established and verified. The results show that when the temperature is lower than 880°C and the strain rate is higher than 0.01s_^-1, the material exhibits obvious dynamic softening. When the temperature is higher than 920°C and the strain rate is lower than 0.001s_^-1, the coarse grain leads to flow stress increasing. It is indicated that the strain, strain rate and deformation temperature all have different effects on grain size, shape and phase content. In addition, it is confirmed that the strain-corrected Arrhenius constitutive equation has higher prediction accuracy, and its MSE is 2.443 and the R value is 0.9675.