基于Murty准则的ZnAl10Cu2合金热变形机制及工艺优化  

Hot deformation mechanism and process optimization for ZnAl10Cu2 alloy based on Murty criterion

作　　者：邬小萍[1] 李德富[1] 郭胜利[1] 许晓庆[1] 胡捷[1] 贺金宇[1] 

机构地区：[1]北京有色金属研究总院,北京100088

出　　处：《中国有色金属学报》2012年第1期80-89,共10页The Chinese Journal of Nonferrous Metals

基　　金：国家"十一五"科技支撑计划资助项目(2009BAE71B03)

摘　　要：在Gleeble-1500D热模拟机上研究了ZnAl10Cu2合金在变形温度为180～330℃、应变速率为0.01～10 s-1、最大变形量为0.7条件下的热变形行为,采用动态材料模型的Murty失稳准则绘制了ZnAl10Cu2合金的热加工图,结合微观组织观察研究了该合金在实验条件下的微观变形机制及流动失稳现象,并优化了热变形的工艺参数。结果表明:ZnAl10Cu2合金在高应变速率区域容易发生流变失稳现象,45°剪切开裂、绝热剪切带和局部塑性流动是流动失稳区的主要变形机理,在变形安全区片状α1和α2相均发生了不同程度的球化和扭折,且基体β相发生了动态再结晶,在变形温度为240℃、应变速率为0.1 s-1时,能量耗散率达到峰值,约为53%。The hot deformation behavior of ZnAl10Cu2 alloy was studied by compression testing on a Gleeble-1500D simulator in the temperature range from 180 ℃ to 330 ℃ and true strain rate range from 0.01 s-1 to 10 s-1 at the maximum true strain of 0.7.A processing map was developed on the basis of Murty instability criterion of dynamic material model.The micro-deformation mechanism and the flow instability phenomena of ZnAl10Cu2 alloy were studied by the microstructure under the experimental conditions,and the optimum processing parameters were evaluated.The results show that ZnAl10Cu2 alloy exhibits flow instability at high strain rate.The 45° shear cracking,adiabatic shear band and the local plastic flow are the main deformation mechanisms.The globalization and kinking of the laminar α1 and α2 phases are observed in the stable domain,and the dynamic recrystallization of β phase is also observed in the stable domain.At deformation temperature of 240 ℃ and strain rate of 0.1 s-1,the power dissipation rate reaches the peak,which is about 53%.

关 键 词：ZnAl10Cu2合金 热加工图 显微组织 绝热剪切带 球化 

分 类 号：TB331[一般工业技术—材料科学与工程]