复杂应变路径加载下7075-T6铝合金的损伤演化  

Damage evolution on 7075-T6 aluminum alloy under complex strain path loading

作　　者：郑唐杰 李贵[1,2,3] 许成 方学彬 Zheng Tangjie;Li Gui;Xu Cheng;Fang Xuebin(Key Laboratory of Metallurgical Equipment and Control Technology,Education Ministry,Wuhan University of Science and Technology,Wuhan 430081 China;Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering,Wuhan University of Science and Technology,Wuhan 430081,China;Precision Manufacturing Institute,Wuhan University of Science and Technology,Wuhan 430081,China)

机构地区：[1]武汉科技大学冶金装备及其控制教育部重点试验室,湖北武汉430081 [2]武汉科技大学机械传动与制造过程湖北省重点试验室,湖北武汉430081 [3]武汉科技大学精密制造研究院,湖北武汉430081

出　　处：《锻压技术》2022年第12期227-233,共7页Forging & Stamping Technology

基　　金：华中科技大学材料成形与模具技术国家重点实验室开放基金资助项目(P2020-019)。

摘　　要：以7075-T6高强铝合金为研究对象,探明其在复杂应变路径加载后的力学性能,设计了可调节变形量的复杂应变装配模型,并基于GTN本构模型进行了单向拉伸和复杂应变路径加载下单向拉伸的仿真模拟,研究了不同变形量对仿真试样的位移-载荷曲线和真实应力-真实应变曲线的影响,分析了f_(O)、f_(N)、f_(C)、f_(F)这4个孔洞体积分数对复杂应变路径加载下试样的真实应力-真实应变曲线的影响。结果表明:在施加复杂应变路径后,试样断裂处所受的应力减小,应变大幅减小;fO和fC主要影响曲线的颈缩阶段,f_(N)主要影响曲线的屈服阶段,而fF对曲线的影响较小。结果显示,相较于单向拉伸的仿真结果,复杂应变路径加载下的真实应力-真实应变曲线能更准确地反映汽车覆盖件在冲压生产过程中的损伤演化过程。For 7075-T6 high-strength aluminum alloy,the mechanical properties after loading in complex strain paths were ascertained,and complex strain assembly model with adjustable deformation was designed.Based on the GTN constitutive model,the simulations of uniaxial tension and uniaxial tension under complex strain path loading were carried out,respectively,the influences of different deformations on the displacement-load curve and true stress-true strain curve for simulated specimen were studied,and the influences of four void volume fractions of f_(O)、f_(N)、f_(C)、f_(F) on the true stress-true strain curve for specimen under complex strain path loading were analyzed.The results show that after applying complex strain paths,the stress and strain at fracture site of sample decrease greatly.fO and fC mainly affect the necking stage of the curve,fN mainly affects the yield stage of the curve,while f_(F) has little effect on the curve.The results show that compared with the simulation results of uniaxial tension,the true stress-true strain curve under complex strain path loading is more accurate for the damage evolution process of automotive panels during the stamping production process.

关 键 词：7075-T6铝合金 损伤模型 复杂应变路径 孔洞体积分数 单向拉伸 

分 类 号：TG115.5[金属学及工艺—物理冶金]