回复与再结晶过程的Monte Carlo模拟研究

考虑回复机制,在原再结晶模型的基础上建立了一个考虑回复过程的Monte Carlo退火模型,并应用该模型模拟了冷轧纯铝板的退火过程。模拟结果与现有再结晶理论相一致:回复过程储存能的降低延缓了再结晶动力学;压下率的增大及退火温度的升高会缩短再结晶孕育期,提高再结晶速度。

完全再结晶区多道次变形时晶粒的变化

含微量钛的16Mn钢在奥氏体完全再结晶区进行恒温、恒道次变形量和恒道次间隙时间的多道次变形后奥氏体晶粒变化的研究,发现多道次变形后奥氏体晶粒尺寸会达到一个极限尺寸,达到极限尺寸所需总变形量和达到的极限晶粒尺寸因变形条件而异。变形温度越高达到所需总变形量Rorit越小,达到的越大,道次变形量越大,达到所需总变形量越大,达到的越小,道次间隙时间的影响小。根据实验结果,提出了在奥氏体完全再结晶区控制轧制该钢种时的合理工艺制度是要保征在950℃左右有2道次以上,道次变形量为20％的变形。

Static recrystallization process comparison of AZ31 magnesium alloy deformed by cold compression and cold forging

We deformed AZ31 magnesium alloys by cold forging and cold compression process,and investigated their static recrystallization kinetics during the annealing process.The results demonstrate that the relationship between the annealing time and the fraction of recrystal grains can be described by the Johnson-Mehl-Avrami-Kolmogorov(JMAK)equation.Based on the kinetics analysis,we calculated that the activation energy of recrystallization by cold forging and cold compression were about 53.5 kJ/mol and 85.0 kJ/mol,respectively.The activation energy of cold compression process was higher than that of the cold forging process because the latter had high-rate deformation,which caused more energy storage during deformation.