采用Gleeble-3800型热力模拟试验机, 在温度为1 123～1 423K、应变速率为0.01～10 s－1的条件下, 对40CrNi2MoE钢进行了高温轴向单道次压缩变形试验, 根据压缩试验结果绘制了高温塑性流变曲线, 并观察了变形后的显微组织。结果表明: 该钢的流变应力和峰值应变随着变形温度的升高和应变速率的降低而减小; 在真应变为0.9, 应变速率为0.01～10 s－1的条件下, 随着应变速率的提高, 其发生完全动态再结晶的温度也逐渐升高; 当应变速率为10 s－1, 变形温度高于1 323 K时, 该钢才会发生完全动态再结晶; 计算得到40CrNi2MoE钢的热变形激活能为333.726 kJ·mol－1, 并建立了该钢动态再结晶条件下峰值应变与Zener-Hollomon因子的定量关系以及高温塑性变形本构方程。

High temperature single-pass compression tests for 40CrNi2MoE steel was carried out on Gleeble-3800 simulator at the temperatures range of 1 123-1 423 K and the strain rate of 0.01-10 s-1. Based on the data of compression tests, the high temperature flow stress curves of 40CrNi2MoE steel were plotted, and the microstructure of the steel after deformation were observed. The results show that the flow stress and peak strain of the 40CrNi2MoE steel decreased with the decrease of strain rate and with the increase of deformation temperature. When the true strain was 0.9 and the range strain rate was 0.01-10 s-1, the full dynamic recrystallization temperature increased with the strain rate rising. When the strain rate was 10 s-1 and the deformation temperature was beyond 1 323 K, full dynamic recrystallization happened in the steel. The hot deformation activation energy of 40CrNi2MoE steel was 333.726 kJ·mol-1 by calculation. Then the hot plastic deformation constitutive equation and the relationship between the peak strain and Zener-Hollomon parameter were established.