基于应变补偿的Al-Zn-Mg合金热变形行为及全应变本构模型  

Hot deformation behavior and total strain constitutive model of Al-Zn-Mg alloy based on strain compensation

作　　者：于春鹏[1] 汤贞涛 李辉[1,2] 陈丽丽 YU Chun-peng;TANG Zhen-tao;LI Hui;CHEN Li-li(Scientific Research Office,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]烟台南山学院科研处,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8期153-158,共6页Journal of Plasticity Engineering

基　　金：山东省重点研发计划项目(2019GGX102025);龙口市科技计划项目(2017GG23)。

摘　　要：利用Gleeble-3500热模拟试验机对Al-Zn-Mg合金进行单道次热压缩试验,获得其在变形温度350~500℃、应变速率0.01~10 s^-1下的应力-应变曲线。对热变形曲线进行摩擦修正,并基于Arrhenius方程建立全应变本构模型,以预测热变形力学行为。结果表明,变形温度及应变速率对热变形力学行为有重要影响,流变应力随变形温度的降低及应变速率的升高而显著升高。位错运动主导的动态回复软化及材料内部晶粒动态再结晶主导的再结晶软化的启动,是抵消加工硬化的主要机制。所建立的全应变本构模型的流变应力预测值与试验值吻合较好,平均相对误差为3.75%,相关系数为0.99。Single-pass hot compression tests of Al-Zn-Mg alloy were carried out on Gleeble-3500 thermal simulator,and the stress-strain curves at temperature of 350-500 ℃ and strain rate of 0. 01-10 s^-1 were obtained. The friction correction of hot deformation curve was carried out,and a total strain constitutive model was established based on the Arrhenius equation to predict the mechanical behavior of hot deformation. The results show that the deformation temperature and strain rate have great influence on hot deformation behavior,the flow stress increases significantly with the decrease of deformation temperature and the increase of strain rate. The initiate of dynamic recovery softening dominated by dislocation movement and recrystallization softening dominated by dynamic recrystallization in grain is the main mechanism to offset work hardening. The flow stress predicted by established constitutive model is in good agreement with the experimental value,the relative average error is 3. 75 % and the relative coefficient is 0. 99.

关 键 词：AL-ZN-MG合金 应变补偿 本构方程 热变形 

分 类 号：TG156.93[金属学及工艺—热处理]