中文摘要：

采用Gleeble-3500热模拟试验机对AZ31镁合金挤压板坯进行平面应变压缩实验,研究镁合金二次变形条件下的热变形行为。结果表明,AZ31镁合金挤压板坯二次变形中发生明显的动态再结晶,进一步细化了再结晶晶粒,且二次变形削弱了挤压板坯的(0002)基面织构强度。DEFORM 3D有限元模拟结果表明,当应变速率一定时,变形温度是决定再结晶晶粒大小的主要因素,而当变形温度一定时,高应变速率所引起的显著温升不利于应变累积,因而再结晶晶粒细化效果并不明显。

英文摘要：

The plain strain compression experiment of AZ31 magnesium extruded sheet was performed on thermal simulation machine Gleeble-3500 in order to investigate the secondary deformation behavior. The results show that the dynamic recrystallization occurs during the secondary deformation of AZ31 magnesium extruded sheet, resulting in the further refinement of grain size of extruded sheet and the weakening of (0002) basal texture. The numerical simulation based on DEFORM 3D shows that the recrystallized grain size depends strongly on the deformation temperature at a constant strain rate, while at a constant deformation temperature, the higher temperature increment resulted from the higher strain rate is unfavorable for the accumulation of strain and then reduces the effect of secondary deformation on the grain refinement.