The isothermal compression test for Ti–6Al–7Nb alloy was conducted by using Gleeble-3800 thermal simulator. The hot deformation behavior of Ti–6Al–7Nb alloy was investigated in the deformation temperature ranges of 940–1030 °C and the strain rate ranges of 0.001–10 s⁻¹. Meanwhile, the activation energy of thermal deformation was computed. The results show that the flow stress of Ti–6Al–7Nb alloy increases with increasing the strain rate and decreasing the deformation temperature. The activation energy of thermal deformation for Ti–6Al–7Nb alloy is much greater than that for self-diffusion of α-Ti and β-Ti. Considering the influence of strain on flow stress, the strain-compensated Arrhenius constitutive model of Ti–6Al–7Nb alloy was established. The error analysis shows that the model has higher accuracy, and the correlation coefficient r and average absolute relative error are 0.9879 and 4.11%, respectively. The processing map (PM) of Ti–6Al–7Nb alloy was constructed by the dynamic materials model and Prasad instability criterion. According to PM and microstructural observation, it is found that the main form of instability zone is local flow, and the deformation mechanisms of the stable zone are mainly superplasticity and dynamic recrystallization. The optimal processing parameters of Ti–6Al–7Nb alloy are determined as follows: 960–995 °C/0.01–0.18 s⁻¹ and 1000–1030 °C/0.001–0.01 s⁻¹.

使用Gleeble-3800热模拟器对Ti-6Al-7Nb合金进行了等温压缩试验。研究了Ti-6Al-7Nb合金在940-1030°C的变形温度范围和0.001-10 s ^-1的应变速率范围内的热变形行为。。同时，计算了热变形的活化能。结果表明，Ti–6Al–7Nb合金的流变应力随着应变率的增加和变形温度的降低而增加。Ti-6Al-7Nb合金的热变形活化能远大于α-Ti和β-Ti自扩散的活化能。考虑到应变对流动应力的影响，建立了Ti-6Al-7Nb合金的应变补偿Arrhenius本构模型。误差分析表明该模型具有较高的精度，相关系数r平均绝对相对误差分别为0.9879和4.11％。利用动态材料模型和Prasad失稳准则建立了Ti-6Al-7Nb合金的加工图（PM）。根据粉末冶金和显微组织观察，发现失稳区的主要形式为局部流动，稳定区的变形机理主要为超塑性和动态再结晶。确定Ti-6Al-7Nb合金的最佳加工参数如下：960-995°C / 0.01-0.18 s ^-1和1000-1030°C / 0.001-0.01 s ^-1。