中文摘要：

利用MMS-300型热模拟试验机对铌钛和铌钛钼两种微合金钢进行了单道次压缩试验，研究了两种钢的热变形行为，分析了微合金元素钼和不同变形条件对其动态再结晶的影响，得到了两种钢的动态再结晶激活能和变形抗力模型。结果表明：随着变形温度（800－1150℃）的降低和应变速率（0．1-10s^-1）的升高，试验钢的变形抗力升高；添加微合金元素钼后，试验钢的变形抗力增大，动态再结晶激活能增大，动态再结晶被抑制，变形温度对变形抗力的影响增大。

英文摘要：

Single compression tests were carried out for Nb-Ti and Nb-Ti-Mo microalloyed steels by using MMS-300 thermal simulation tester. The hot deformation behavior of the steels and the effects of Mo and deformation conditions on dynamic recrystallization had been studied. The dynamic recrystallization activation energy and the models for deformation resistance of the steels were obtained. The results show that the deformation resistance of the tested steel increased with the deformation temperature decreasing （800-1 150 ℃ ） and strain rate inereasing （0. 1 - 10 s^-1 ）. Microalloying element Mo addition produced a increase for deformation resistance and re.crystallization activation energy, a retardation for dynamic recrystallzation, and the effect of deformation temperature on deformation resistance increased.