挤压态ZK60镁合金棒材的热变形行为  

Thermal Deformation Behavior of Extruded ZK60 Magnesium Alloy

作　　者：于仁杰 梁海成[1] 张玉鹏 崔海涛[1] YU Renjie;LIANG Haicheng;ZHANG Yupeng;CUI Haitao(Shenyang Ligong University,Shenyang 110159,China)

机构地区：[1]沈阳理工大学材料科学与工程学院,沈阳110159

出　　处：《沈阳理工大学学报》2021年第4期53-59,共7页Journal of Shenyang Ligong University

基　　金：辽宁省教育厅科学研究经费项目(LG202010)。

摘　　要：采用MMS-200热力模拟试验机对挤压态ZK60镁合金棒材进行热压缩实验,为ZK60镁合金热压缩变形时合理选择参数范围提供理论指导。分析应变速率、变形温度和流变应力之间的关系;构建ZK60镁合金流变应力本构方程;采用金相显微镜观察微观组织演化规律。结果表明:峰值应力随着应变速率的提高和变形温度的降低而增大,且真应力-真应变曲线中表现出动态再结晶的特征;在给定参数下,通过本构方程计算得到ZK60镁合金的变形激活能Q为128.91kJ/mol,应力指数n为4.8519;降低变形温度、提高应变速率有助于减小再结晶晶粒的平均尺寸。The hot compression experiments of extruded ZK60 magnesium alloy bars are carried out on MMS-200 thermal simulation machine.The aim is to provide theoretical guidance for selecting reasonable parameter range during hot compression deformation of ZK60 magnesium alloy.The relationship between strain rate deformation temperature and flow stress is analyzed.The flow stress constitutive equation of ZK60 magnesium alloy is established.The microstructure evolution is observed by metallographic microscope.The results show that the peak stress increases with the increase of strain rate and the decrease of deformation temperature, and the true stress-true strain curves show the characteristics of dynamic recrystallization.In a given parameter, the deformation activation energy Q of ZK60 magnesium alloy which is calculated by the constitutive equation is 128.91 kJ/mol, stress exponent is 4.8519.The average size of recrystallized grains can be reduced by decreasing the deformation temperature and increasing the strain rate.

关 键 词：ZK60镁合金 热压缩 应力-应变曲线 动态再结晶 本构方程 

分 类 号：TG146.2[一般工业技术—材料科学与工程]