基于本构方程和热加工图的Al-xMg-2.8Zn合金的热变形行为研究  

Study on Hot Deformation Behavior of Al-xMg-2.8Zn Alloy by Constitutive Equations and Processing Maps

作　　者：姚晶晶 张迪[1,2] 张济山[1,2] Yao Jingjing;Zhang Di;Zhang Jishan(State Key Laboratory of Advanced Metals and Materials,University of Science and Technology Beijing,Beijing 100083,China;Beijing Laboratory of Metallic Materials and Processing for Modern Transportation,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]北京科技大学新金属材料国家重点实验室,北京100083 [2]北京科技大学现代交通金属材料与加工技术北京实验室,北京100083

出　　处：《稀有金属材料与工程》2022年第6期2046-2055,共10页Rare Metal Materials and Engineering

基　　金：Major State Research and Development Program of China(2016YFB0300801);National Natural Science Foundation of China(51971019,51571013)。

摘　　要：通过热压缩模拟试验研究了Al-xMg-2.8Zn合金在变形温度为300~490℃、应变速率为0.001~5 s^(-1)条件下的热变形行为。修正了应变-应力曲线中由于变形热引起的流动软化现象后,利用Arrhenius本构方程和热加工图预测并分析了Al-xMg-8Zn合金的热变形行为。结果表明,随着Mg含量的增加,应变速率的升高,或者变形温度的降低,流变应力随之增大。结合热加工图和微观组织观察,确定了合金的最佳热加工参数范围。通过对比发现,随着Mg含量的增加,最佳热变形温度和应变速率范围均变大,变形失稳区域向高温和低应变速率区域扩展。The hot deformation behavior of Al-xMg-2.8 Zn alloys at deformation temperature of 300~490℃,strain rate of 0.001~5 s^(-1)was studied by isothermal hot compression tests.After correcting the flow softening from deformation heating in stress-strain curves,Arrhenius-type constitutive equations and processing maps were used to predict and analyze the hot deformation behavior of Al-xMg-2.8 Zn alloys.The results show that the flow stress increases with increasing Mg content and strain rate or decreasing temperature.According to the processing maps and corresponding microstructure of alloys,the range of optimum hot deformation parameters of alloys is determined.The range of hot deformation temperature and strain rate both extend and the instability domains extend to the zone of higher temperature and lower strain rate with increasing the Mg content.

关 键 词：Al-Mg-Zn合金 热变形行为 本构方程 热加工图 

分 类 号：TG146.21[一般工业技术—材料科学与工程]