车身用新型Al-Zn-Mg铝合金热变形本构方程及热加工图  

Hot deformation constitutive equation and hot processing map of novel Al-Zn-Mg aluminum alloy for automobile body

作　　者：曲世永[1] 李民[1] 吕正风 房洪杰[1] QU Shi-yong;LI Min;Lü Zheng-feng;FANG Hong-jie(College of Engineering,Yantai Nanshan University,Yantai 265713,China;National Engineering Research Center for Plastic Working of Aluminum Alloys,Shandong Nanshan Aluminum Co.,Ltd.,Yantai 265700,China)

机构地区：[1]烟台南山学院工学院,山东烟台265713 [2]山东南山铝业股份有限公司,国家铝合金压力加工工程技术研究中心,山东烟台265700

出　　处：《塑性工程学报》2020年第9期161-166,共6页Journal of Plasticity Engineering

基　　金：山东省重点研发计划项目(2019GGX102025);山东省高等学校青创科技计划项目(2019KJA019)。

摘　　要：设计了一种汽车车身结构件用Al-Zn-Mg中强铝合金,利用Gleeble-3500热模拟试验机测试了该合金在不同热变形条件下的应力-应变曲线,构建了峰值应力本构方程,绘制了不同应变量下合金的热加工图。结果表明:Al-Zn-Mg铝合金热变形过程呈现正的应变速率敏感性和负的温度敏感性;建立的以Z参数表示的Arrhenius本构方程所预测的峰值应力与实验值平均相对误差为8.4%,线性相关系数为0.987,说明拟合情况良好;根据不同应变量下的热加工图,发现流变失稳区及功率耗散低谷区均集中在高温高应变速率区和低温低应变速率区,且随着应变量的增大均逐渐缩小,最佳热变形工艺参数范围为350~500℃,0.01~0.1 s^-1。Al-Zn-Mg aluminum alloy with medium strength for auto body structural part was designed,and the Gleeble-3500 thermal simulator was used to test the stress-strain curves of the alloy under different hot deformation conditions. The peak stress constitutive equation was established and the hot processing maps under different strains were drawn. The results show that the hot deformation process of the Al-Zn-Mg aluminum alloy shows positive strain rate sensitivity and negative temperature sensitivity. The average relative error between the predicted peak stress value by the established Arrhenius constitutive equation represented with parameter Z and experimental value is8. 4%,and the linear relative coefficient is 0. 987,which indicates the fitting situation is good. The rheological instability zone and power dissipation trough zone were focused on the high temperature-high strain rate zone and low temperature-low strain rate zone according to the hot processing maps under different strains,and diminishes gradually with the increase of strain. The optimal range of hot deformation process parameters is 350-500 ℃,0. 01-0. 1 s^-1.

关 键 词：Al-Zn-Mg铝合金 热变形行为 本构方程 热加工图 

分 类 号：TG389[金属学及工艺—金属压力加工]