AZ31镁合金薄板动态再结晶对其拉伸性能的影响  

Effect of dynamic recrystallization on tensile properties of AZ31 magnesium alloy sheet

作　　者：胡丽娟[1] 彭颖红[1] 唐伟琴[1] 李大永[1] 张少睿[1] 

机构地区：[1]上海交通大学机械与动力工程学院,上海200240

出　　处：《中国有色金属学报》2008年第9期1571-1576,共6页The Chinese Journal of Nonferrous Metals

基　　金：国家重点基础研究发展计划基础预研资助项目(2006CB708611);上海科委资助项目(06dj14005;06QA14026)

摘　　要：基于热粘塑性本构理论,构建拉伸动态再结晶理论模型,并将该模型引入AZ31镁合金薄板变温拉伸的数值仿真。通过数值仿真分析AZ31镁合金薄板动态再结晶对其拉伸性能的影响。采用Gleeble3500热模拟试验机对AZ31镁合金薄板在定应变速率为0.25/s、不同温度(473、523、573和673K)条件下进行单向拉伸实验,并利用光学显微镜观察变形中合金微观组织的演变。结果表明:随着镁合金薄板变形温度的升高,动态再结晶晶粒数量逐渐增加,尺寸先增后减,同时分布更趋于均匀;单向拉伸时,动态再结晶导致镁合金板材出现动态软化现象,流动应力降低。On the basis of thermoviscoplastic theory, the dynamic recrystallization （DRX） model of tension was constructed. This model was introduced into the finite element analysis of tension of AZ31 magnesium alloy sheet by changing temperature. The effect of DR.X on the tensile properties of AZ31 magnesium alloy sheet was analyzed by numerical and experimental methods. The uniaxial tensile tests were conducted using a Gleeble 3500 thermal-mechanical simulator under fixed strain rate and various temperatures. The true strain-stress curves were obtained, and the microstructures of AZ31 magnesium alloy sheet were analyzed. The results show that the number of DRX grains increase gradually with the increase of temperature. The DRX grain size increases first and then decreases, and the DRX grain distribution of magnesium alloy sheet is more well-distributed. During the plastic deforming, magnesium alloy sheet is softened due to DRX and the flow stress is reduced.

关 键 词：动态再结晶 热粘塑性本构 微观组织 拉伸性能 

分 类 号：TG115[金属学及工艺—物理冶金]