中文摘要：

利用Gleeble-1500D热模拟试验机对Ce微合金化IF钢在变形温度790～950℃,应变速率0.1～5 s-1,变形量50%条件下进行了单道次压缩试验,研究了变形条件对试验钢热变形行为的影响,结合热模拟组织金相分析及双曲正弦本构方程、动态再结晶动力学方程分析了钢中Ce含量对IF钢动态再结晶行为的影响。结果表明：随着变形温度的降低和应变速率的增加,试验钢的变形抗力增大;添加Ce后,试验钢的热变形激活能增大,由122.92 kJ·mol^-1增加到182.75 kJ·mol^-1;Avrami方程指数kd由3.796减小到3.377,动态再结晶分数Xd也相应减小,动态再结晶被抑制,并随着钢中Ce含量的增加,抑制作用越显著。

英文摘要：

The influence of deformation condition on hot deformation behavior of Ce microalloyed IF steel was investigated via the single compression tests on a Gleeble-1500D thermomechanical simulator at temperature range of 790 ～ 950 ℃,strain rate range of 0. 1 ～ 5 s^-1 and deformation of 50%. The effect of Ce on dynamic recrystallization behavior was analyzed by detection of microstructure,hyperbole sine constitutive equation and dynamic recrystallization kinetics equation. The experimental results showed that the deformation resistance of the investigated steels increased with the deformation temperature decreasing and strain rate increasing. The nominal activation energy of dynamic recrystallization was increased from 122. 92 to 182. 75 kJ·mol^-1 and the Avrami equation index was decreased from 3. 796 to 3. 377,meanwhile the dynamic recrystallization fraction was reduced accordingly. It could be concluded that Ce restrained the dynamic recrystallization and the more dissolved Ce in steel,the more inhibition effect was.