(昆明理工大学 材料科学与工程学院 云南省新材料制备与加工重点实验室，昆明 650093)
摘 要: 采用Gleeble-1500热模拟试验机研究Pb-Mg-Al合金在变形温度453~613 K、应变速率0.01~1 s-1条件下的热压缩流变行为，计算应力指数和变形激活能，采用Zener-Hollomon参数法构建合金的高温变形的本构关系，基于Murty准则，建立Pb-Mg-Al合金的加工图。结果表明：Pb-Mg-Al合金为正应变速率敏感材料；该合金的热压缩变形流变应力行为可用双曲正弦函数本构方程和Zener-Hollomon参数来描述，其平均变形激活能为149.524 4 kJ/mol；从加工图分析并结合激活能，确定Pb-Mg-Al合金的最优变形温度和应变速率分别为533 K和0.1 s-1。
关键字: Pb-Mg-Al合金；本构关系；变形激活能；加工图
（Key Laboratory of Advanced Materials of Yunnan Province, Faculty of Material Science and Engineering,
Kunming University of Science and Technology, Kunming 650093, China）
Abstract:The flow stress behaviors and the deformation microstructure of hot compressed Pb-Mg-Al alloy were investigated by hot compressive tests on Gleeble-1500 thermo-simulation machine in the temperature range of 453-613 K and strain rates range of 0.01-1 s-1. The stress exponent and deformation activation at elevated temperatures were calculated. The constitutive relationship of the Pb-Mg-Al alloy during hot compression deformation at high temperatures was obtained by introducing Zener-Hollomon parameter. Based on Murty criterion, the processing map for the Pb-Mg-Al alloy was obtained. The results show that Pb-Mg-Al alloy is sensitive to strain rate. The hot deformation behavior can be described by a constitutive equation in hyperbolic sine function and Zener-Hollomon parameter. The average hot deformation activation energy of Pb-Mg-Al alloy is 149.524 4 kJ/mol. The optimal processing parameters derived from processing map and activation energy are 533 K in temperature and 0.1 s-1 in strain rate.
Key words: Pb-Mg-Al alloy; constitutive relationship; deformation activation energy; processing map
