不同应变速率下Al-Zn-Mg-Cu铝合金的变形行为及微观组织演变  

Deformation behavior and microstructure evolution of Al-Zn-Mg-Cu aluminum alloy with different strain rates

作　　者：吴晓冬 肖罡[2,3] 王文韫 韦春华 许征兵[4] WU Xiao-dong;XIAO Gang;WANG Wen-yun;WEI Chun-hua;XU Zheng-bing(School of Information Science&Engineering,Changsha Normal University,Changsha 410205,China;State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body,Hunan University,Changsha 410082,China;School of Mechanical and Electrical Engineering,Central South University,Changsha 410083,China;MOE Key Laboratory of New Processing Technology for Non-ferrous Metals and Materials/Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials,Guangxi University,Nanning 530004,China)

机构地区：[1]长沙师范学院信息科学与工程学院,湖南长沙410205 [2]湖南大学汽车车身先进设计制造国家重点实验室,湖南长沙410082 [3]中南大学机电工程学院,湖南长沙410083 [4]广西大学有色金属及材料加工新技术教育部重点实验室/广西有色金属及特色材料加工重点实验室,广西南宁530004

出　　处：《塑性工程学报》2022年第10期188-195,共8页Journal of Plasticity Engineering

基　　金：国家自然科学基金面上资助项目(52075159);湖南省自然科学基金资助项目(2022JJ30019,2020JJ5187);国家金属材料近净成形工程技术研究中心开放基金资助项目(2020013);广西大学有色金属及特色材料加工重点实验室开放基金项目(2022GXYSOF24)。

摘　　要：采用万能试验机和霍普金森杆研究了Al-Zn-Mg-Cu铝合金在应变速率为0.001~5000 s^(-1)下的变形行为,求解并优化了Johnson-Cook本构方程,分析了微观组织演变与变形行为的关联。结果表明,准静态加载作用下铝合金存在拉伸-压缩不对称性,且应变速率效应不明显,动态压缩载荷下有明显的应变硬化现象,且有正应变速率效应。修正应变速率敏感系数后的Johnson-Cook本构方程可以较好地对该铝合金的变形行为进行预测。动态加载下铝合金内部晶粒的细化、位错密度的增加和析出相的演变导致了正应变速率效应。The deformation behavior of Al-Zn-Mg-Cu aluminum alloys was studied using the universal testing machine and Hopkinson bars with strain rate of 0.001-5000 s^(-1),and the Johnson-Cook constitutive equation was solved and optimized,and the correlation between microstructure evolution and deformation behavior was analyzed.The results show that there is tensile-compression asymmetry of the aluminum alloy under quasi-static loading and the strain rate effect is not obvious,and there is obvious strain hardening phenomenon with positive strain rate effect under dynamic compression loading.The Johnson-Cook constitutive equation with modified strain rate sensitivity coefficient can better predict the deformation behavior of the aluminum alloy.Under dynamic loading,the refinement of internal grain of the aluminum alloys,the increase of dislocation density and the evolution of precipitated phases lead to the positive strain rate effect.

关 键 词：铝合金 应变速率 变形行为 本构关系 组织演变 

分 类 号：U465[一般工业技术—材料科学与工程]