Abstract: Thermal compression test of C630R rotor steel was carried out by Gleeble-3800 thermal simulation testing machine at temperature range of 1 000-1 200 ℃ and strain rate of 0.01-1 s^-1， the thermal deformation behavior and the influence of different process parameters on the microstructure were studied， the constitutive equation and hot processing map of the C630R rotor steel at true strain of 0.8 was constructed. The experimental results indicate that the true stress of the C630R rotor steel decreases with the enhancement of deformation temperatures to 1 200 ℃ and the reduction of true strain rate to 0.01 s^-1. When the deformation temperature is higher and the compression strain rate is lower， C630R rotor steel is preferred to produce dynamic recrystallization. Thermal deformation activation energy Q of the C630R rotor steel is calculated to be 530.155 kJ/mol by using the corrected flow stress curves， and the constitutive equation is  ε= 5. 85 × 1018[sinh (0. 011 4σ) ]4. 852∙ exp (-530 155/RT）），the processing maps at true strain of 0.8 are plotted．The reasonable thermal processing parameters for C630R rotor steel under true strain of 0.8 is： deformation temperature of 1 075-1 200 ℃， strain rate of 0.01-0.11 s^-1.

Key words: C630R Rotor Steel, Deformation Temperatures, Strain Rate, Constitutive Equation, Hot Processing Map

摘要： 通过Gleeble-3800试验机，开展了C630R转子钢在温度1 000～1 200 ℃、应变速率0.01～1 s^-1条件下的热压缩试验，研究了热变形行为及不同工艺参数对其显微组织的影响，计算了C630R转子钢的本构方程，并绘制了真应变为0.8时的热加工图。结果表明，C630R转子钢的流变应力随变形温度升高和应变速率减小而降低；随着变形温度升至1 200 ℃，或者应变速率降至0.01 s^-1，C630R转子钢更倾向于产生动态再结晶。利用修正的流变应力曲线，计算出C630R转子钢的热变形激活能Q 为530.155 kJ/mol，本构方程为为 ε= 5. 85 × 1018[sinh (0. 011 4σ) ]4. 852∙ exp (-530 155/RT），绘制了真应变为0.8时的热加工图。结合显微组织，C630R转子钢在真应变0.8时合理的热加工工艺参数为变形温度1 075～1 200 ℃，应变速率0.01～0.11 s^-1。

关键词: C630R转子钢, 变形温度, 应变速率, 本构方程, 热加工图