Electroplastic effect in AZ31B magnesium alloy sheet through uniaxial tensile tests  

单向拉伸试验研究AZ31B镁合金板材的电塑性效应（英文）

作　　者：解焕阳[1] 王倩[1] 彭芳[1] 刘凯[1] 董湘怀[1] 王建峰 

机构地区：[1]上海交通大学塑性成形技术与装备研究院,上海200030 [2]通用汽车中国科研院,上海201206

出　　处：《Transactions of Nonferrous Metals Society of China》2015年第8期2686-2692,共7页中国有色金属学报（英文版）

基　　金：Projects(50975174,51275297)supported by the National Natural Science Foundation of China;Project(20100073110044)supported by the Education Ministry of China

摘　　要：The electroplastic effect in AZ31B magnesium alloy sheet was investigated through uniaxial tensile tests. In order to show the athermal effect of the electrical pulses, two types of uniaxial tensile tests at the same testing temperature were carried out： uniaxial tension in environmental cabinet and uniaxial tension with electrical pulses. In addition, the distribution of temperature field in the cross-section area during uniaxial tension with electrical pulses was simulated. The results show that the distribution of temperature field along the cross-section area is homogeneous. By comparing the true stress？true strain curves of AZ31B alloy under uniaxial tensile tests, the athermal effect with electrical pulses was confirmed. The microstructure evolution after the uniaxial tension was studied by optical microscopy. The results indicate that the electrical pulses induced dynamic recrystallization plays an important role in the decrease of flow stress. Finally, a flow stress model of AZ31B sheet taking the influence of electroplastic effect into account was proposed and validated. The results demonstrate that the calculated data fit the experimental data well.通过单向拉伸试验研究镁合金AZ31B的电塑性效应。为了显示脉冲电流的非热效应,在相同温度下开展两类试验:环境箱中的单向拉伸试验和脉冲电流辅助的单向拉伸试验。此外,对脉冲电流在材料变形过程中引起的温度场进行数值模拟。结果表明,沿材料截面方向温度分布均匀。通过对比两类单向拉伸试验的真应力-真应变曲线,证实了脉冲电流非热效应的存在。通过光学显微镜研究脉冲电流对材料微观组织演化的影响,结果表明:脉冲电流引起的动态再结晶对流动应力的下降起重要作用。最后,提出一个考虑电塑性响应的AZ31B流动应力模型,并通过实验进行验证。结果表明:模型预测结果和实验结果吻合较好。

关 键 词：AZ31B magnesium alloy sheet electroplastic effect temperature field simulation microstructure evolution 

分 类 号：TG146.22[一般工业技术—材料科学与工程]