30CrMnSi钢的热变形行为与晶粒演化特征

Hot Deformation Behavior and Grain Evolution of Steel 30CrMnSi

对于初始粗晶的高强钢30CrMnSi进行了圆柱体热压缩实验研究，获得了该种材料在不同温度不同应变速率条件下的真应力一应变曲线以及动态再结晶和晶粒细化的规律。应用峰值应力的实验结果计算出了该材料热变形过程的激活能以及每个实验条件的Z参数，得到了高强钢30CrMnSi的热变形过程以及动态再结晶过程的主要特征变量作为Z参数的函数表达式。发现在z参数=1．0E＋12／s～1．OE＋13／s、工程应变一60％的条件下动态再结晶会产生较好的晶粒细化效果。

An experimental study on hot compression deformation of cylindrical specimen ofhigh strength steel 30CrMnSi with initial coarse grains is carried out in this paper. The experimental results include the true stress -true strain curves under different temperature and different strain rate, the data on dynamic recrystallization process and grain refinement. By using the experimental data on peak stress the activation energy of the hot deformation is obtained and then the Zener-- Hollomon parameters corresponding to different experimental conditions are also obtained. The mathematic expressions of the variables describing hot deformation and microstructure evolution, as the function of the Z parameter, are given in this paper. The experimental results show that a better grain refinement can be reached when Z= 1.0E＋ 12/s～ 1.0E＋ 13/s and compression strain =60%.