Effect of solution treatment time on plasticity and ductile fracture of 7075 aluminum alloy sheet in hot stamping process  

固溶处理时间对7075铝合金热冲压板材塑性及韧性断裂的影响

作　　者：Hui-cheng GENG Yi-lin WANG Bin ZHU Zi-jian WANG Yi-sheng ZHANG 耿会程;王义林;朱彬;王子健;张宜生(华中科技大学材料成形与模具技术国家重点实验室,武汉430074;苏州大学沙钢钢铁学院,苏州215006)

机构地区：[1]State Key Lab of Materials Processing and Die and Mould Technology,Huazhong University of Science and Technology,Wuhan 430074,China [2]School of Iron and Steel,Soochow University,Suzhou 215006,China

出　　处：《Transactions of Nonferrous Metals Society of China》2022年第11期3516-3533,共18页中国有色金属学报（英文版）

基　　金：the National Natural Science Foundation of China(No.U1760205).

摘　　要：The effect of solution treatment time on the post-formed plasticity and ductile fracture of 7075 aluminum alloy in the hot stamping process was studied.Tensile tests were conducted on the specimens subjected to the hot stamping process with different solution treatment time.The digital image correlation(DIC)analysis was used to obtain the strain of the specimen.Based on the experiments and modeling,the Yld2000-3d yield criterion and the DF2014 ductile fracture criterion were calibrated and used to characterize the anisotropy and fracture behavior of the metal,respectively.Furthermore,the microstructure of specimens was studied.The experimental and simulation results indicate that the 7075 aluminum alloy retains distinct anisotropy after the hot stamping process,and there is no obvious effect of extending the solution treatment time on the material anisotropy.However,it is found that a longer solution treatment time can increase the fracture strain of the aluminum alloy during the hot stamping process,which may be related to the decrease of the second-phase particles size.研究固溶处理时间对7075铝合金热冲压板材塑性及韧性断裂的影响。对采用不同固溶处理时间的热冲压试样进行拉伸实验,并采用数字图像相关分析方法获取实验过程中试样的应变。基于实验及仿真,对Yld2000-3d屈服准则及DF2014断裂模型进行校准,并将其分别用于描述材料的各向异性及断裂行为。同时,对材料的显微组织进行研究。实验及仿真结果表明,热冲压后,7075铝合金仍残留明显各向异性,且延长固溶处理时间不能有效减弱材料的各向异性。但是,采用较长的固溶时间会提高材料的断裂应变,断裂性能的提高与延长固溶处理时间后第二相颗粒尺寸减小有关。

关 键 词：7075 aluminum alloy hot stamping solution treatment time ANISOTROPY ductile fracture 

分 类 号：TG156.92[金属学及工艺—热处理] TG146.21[金属学及工艺—金属学]