低碳高铌X100管线钢的静态软化行为

Static Softening Behavior of Low Carbon High Niobium X100 Pipeline Steel

通过热模拟试验机对低碳高铌X100管线钢进行双道次热压缩试验,研究了其静态软化行为,建立了该管线钢静态再结晶动力学模型。结果表明:该管线钢的静态软化行为受道次间隔时间和变形温度的影响较大;随着变形温度的升高和道次间隔时间的延长,试验钢的静态软化率增大;当变形温度低于950℃时,试验钢不会发生静态再结晶行为,而当变形温度高于1 000℃时,试验钢可以实现完全静态再结晶;通过建立的模型计算得到该钢的静态再结晶激活能为325kJ·mol-1,与采用化学成分经验公式法求得的结果相吻合。

The static softening behavior of low carbon high niobium X100 pipeline steel was studied by double pass hot compression test carried on thermal simulator.The static recrystallization kinetics model of the low carbon high niobium high strength pipeline steel was established.The results show that the static softening behavior of the tested steel was distinctly affected by deformation temperature and interval time.With the increase of deformation temperature and prolongation of the interval time,the static softening rate of the tested steel increased.When the deformation temperature was below 950 ℃,static recrystallization behavior did not occur.When the deformation temperature was higher than 1 000 ℃,the tested steel achieved complete static recrystallization.The activation energy of static recrystallization of the steel was 325 kJ·mol^（-1） which calculated by the kinetics model.And the result was consistent with that calculated by the empirical formula based on the chemical composition.