The warm deformation behavior of 20CrMoA steel at the temperature of 873–1123 K and the strain rate of 0.01−10 s⁻¹ was investigated to obtain its processing property and optimum processing parameters. The true stress-true strain curves showed that flow stress reaches the peak rapidly, followed by slow decrease till reaching a steady state. This suggests a flow softening of dynamic recovery. The stress dropped with increasing deformation temperature and decreasing strain rate. The reduction became more distinct at lower temperature and higher strain rate due to flow softening caused by deformation heat. In the temperature range of 873–973 K, the deformation of 20CrMoA steel was more sensitive to temperature, and the average decline rate of steady stress was 6.9 times larger than that in the temperature range of 1023–1123 K. After modifying the stress curves, a constitutive model was developed for different deformation temperature ranges based on modified curves. The model was in good agreement with the experimental results.

中文翻译：

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20CrMoA钢热变形过程中的流变应力曲线修正与本构模型

20CrMoA钢在873-1123 K温度和0.01-10 s ^-1应变速率下的热变形行为进行了研究以获得其加工性能和最佳加工参数。真实应力-真实应变曲线表明，流动应力迅速达到峰值，然后缓慢减小直至达到稳态。这表明动态恢复的流量软化。应力随着变形温度的升高和应变率的降低而下降。由于变形热引起的流动软化，在较低的温度和较高的应变速率下，还原作用变得更加明显。在873–973 K的温度范围内，20CrMoA钢的变形对温度更加敏感，并且稳态应力的平均下降速率是1023–1123 K的温度范围内的6.9倍。 ，基于修改后的曲线，针对不同变形温度范围开发了本构模型。该模型与实验结果吻合良好。