In order to provide a theoretical basis for hot working technologies, the hot deformation behavior of 13MnNiMoR pressure vessel steel was studied by a single-pass compressive deformation test at elevated temperatures to explore effects of deformation temperature (950~1150℃) and strain rate (0. 01~1 s-1 ) on deformation. The results showed that dynamic recrystallization is easy to occur in austenite when strain rate is lower than 0. 1 s-1 because a new austenite has enough time to nucleate and grow. The main softening mechanism of this steel changes from dynamic recrystallization to dynamic recovery with decreasing temperature and increasing strain rate. Through data fitting, the stress exponent and activation energy for dynamic recrystallization were determined to be 4. 29 and 319 kJ/mol. Finally, the hot working equation of 13MnNiMoR steel was established on the basis of compressive flow stress curves.%为制定中温中压容器用钢13MnNiMoR的热加工工艺提供理论依据并实现其工业化生产,利用单道次热压缩模拟实验研究了变形温度(900~1150℃)和应变速率(0.01~1 s-1)对其热变形行为的影响.结果表明:当应变速率低于0.1 s-1时,新晶粒有足够的时间进行形核和长大,奥氏体容易发生动态再结晶;当变形温度降低或应变速率增加时,实验钢在变形过程中主要发生动态回复,流变应力也随之提高.基于测定的流变应力曲线,通过拟合得到实验钢在热变形时的应力指数为4.29,动态再结晶激活能为319 kJ/mol,据此建立了13MnNiMoR钢在高温变形时的热加工方程.
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