【摘要】 用Gleeble-2000热模拟实验机对实验钢进行高温单道次压缩实验,研究了实验钢动态再结晶行为.实验结果表明:实验钢动态再结晶激活能为304.711 kJ/mol;在较高温度和低应变速率条件下实验钢易于发生动态再结晶,随着lnZ的减小,实验钢应力-应变曲线由动态回复型变为动态再结晶型;当lnZ<22.61时,曲线上出现多个峰值,呈间断式动态再结晶型;峰值应力、峰值应变和临界应变与lnZ呈线性关系;动态再结晶开始时间随着应变速率的增大和温度的升高而缩短.更多还原

【Abstract】 The dynamic recrystallization behavior of the specimens of Nb-microalloyed steel was tested on Gleeble-2000 thermomechanical simulator by way of single pass at high temperature.The results revealed some facts about the specimen as follows.The dynamic recrystallization of which the activation energy 304.711 kJ/mol is liable to occur at higher temperature and lower strain rate,and the stressstrain curve in form of dynamic recovery changes into dynamic recrystallization with decreasing lnZ.The curves present several peaks,which means that it’s in intermittent form of dynamic recrystallization when lnZ<22.61.It’s found that the peak stress/strain and critical strain all bear linear relationship with lnZ.The starting time of dynamic recrystallization decreases with increasing strain rate and temperature.更多还原