回归升温速率对Al-6.02Zn-2.24Mg-2.30Cu合金组织和性能的影响  

Influence of Regression Heating Rates on Microstructure and Propertiesof Al-6.02Zn-2.24Mg-2.30Cu Alloy

作　　者：程全士 高靖靖 贺春花 叶凌英[2] CHENG Quanshi;GAO Jingjing;HE Chunhua;YE Lingying(Henan Key Laboratory of Fastening Connection Technology,Xinyang 464000,China;School of Materials Science and Engineering,Central South University,Changsha 410083,China)

机构地区：[1]河南省紧固连接技术重点实验室,河南信阳464000 [2]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《热加工工艺》2024年第10期137-142,共6页Hot Working Technology

基　　金：国家重点研发计划项目(2016YFB0300901)。

摘　　要：采用室温拉伸、慢应变速率拉伸应力腐蚀和透射电镜等检测手段,研究了回归升温速率对Al-6.02Zn-2.24 Mg-2.30Cu合金组织和性能的影响。结果表明,随着回归升温速率的降低,合金处于高温区时间增加,合金强度不断降低。回归升温速率由5.6℃/min下降到0.25℃/min,抗拉强度由663.1 MPa下降到631.7 MPa,而合金导电率和抗腐蚀性能逐渐增加,应力腐蚀敏感指数由4.7%下降到2.7%。回归升温速率减慢,晶内相长大程度增加,降低了合金强度。但同时晶界析出相尺寸及其分布间距增加,晶界析出相中的Cu含量随之增加,提高了合金的抗腐蚀性能。The effects of regression heating rates on the microstructure and properties of Al-6.02Zn-2.24Mg-2.30Cu alloy were investigated by means of tensile tests at room temperature,slow strain rate stress corrosion and transmission electron microscopy.The results show that with the decrease of the regression heating rate,the time in the region of high temperature increases,the strength of the alloy continuously decreases.When the regression heating rate decreases from 5.6℃/min to 0.25℃/min,the tensile strength decreases from 663.1 MPa to 631.7 MPa,while the conductivity and corrosion resistance of the alloy increase gradually,the index of sensitivity to stress corrosion decreases from 4.7%to 2.7%.The regression heating rate slows down,the growth degree of the inner-grain phase increases,which leads to the decrease of the alloy strength.But at the same time,with the increase of grain boundary precipitates'size and distribution spacing,as well as the Cu content in grain boundary precipitates also increases,which improves the corrosion resistance of the alloy.

关 键 词：Al-6.02Zn-2.24Mg-2.30Cu合金 回归升温速率 应力腐蚀 剥落腐蚀 

分 类 号：TG166.3[金属学及工艺—热处理]