Effects of Aging Temperature on Microstructure and High Cycle Fatigue Performance of 7075 Aluminum Alloy  

作　　者：杨大炼 刘义伦 LI Songbai MA Liyong LIU Chi YI Jiuhuo 

机构地区：[1]Hunan Provincial Key Laboratory of Health Maintenance for Mechanical Equipment, Hunan University of Science and Technology, Xiangtan 411201, China [2]School of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China [3]Light Alloy Research Institute, Central South University, Changsha 410083, China [4]School of Mechanical Engineering, Hebei University of Architecture, Zhangjiakou 075051, China

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2017年第3期677-684,共8页武汉理工大学学报（材料科学英文版）

基　　金：Funded by the National Natural Science Foundation of China(Nos.51375500,and 51375162);Scientific Research Project of Hunan Province Department of Education(No.17C0886);Open Funded Projects of Hunan Provincial Key Laboratory of Health Maintenance for Mechanical Equipment(No.201605)

摘　　要：The hardness, the tensile and the high-cycle fatigue（HCF） performances of 7075 aluminum alloy were investigated under temper T651, solution treated at 380 ℃ for 0.5 h and aged at different temperatures（150, 170, 190 ℃） for 10 hours. The optimal microstructures and the fatigue fracture surfaces were observed. The results show that the hardness and the tensile performances are at their optimum at T651, but the fatigue life is the shortest. The hardness and the elongation are the lowest after solution treatment. With the aging temperature increasing（150-190 ℃）, the HCF is improved. The crack is initiated from the impurity particles on the subsurface. Treated at 170 ℃,the area of the quasi-cleavage plane and the width of parallel serrated sections of the crack propagation are the largest. With increasing aging temperature, the dimple size of finally fracture surfaces becomes larger and the depth deeper.The hardness, the tensile and the high-cycle fatigue（HCF） performances of 7075 aluminum alloy were investigated under temper T651, solution treated at 380 ℃ for 0.5 h and aged at different temperatures（150, 170, 190 ℃） for 10 hours. The optimal microstructures and the fatigue fracture surfaces were observed. The results show that the hardness and the tensile performances are at their optimum at T651, but the fatigue life is the shortest. The hardness and the elongation are the lowest after solution treatment. With the aging temperature increasing（150-190 ℃）, the HCF is improved. The crack is initiated from the impurity particles on the subsurface. Treated at 170 ℃,the area of the quasi-cleavage plane and the width of parallel serrated sections of the crack propagation are the largest. With increasing aging temperature, the dimple size of finally fracture surfaces becomes larger and the depth deeper.

关 键 词：creep aging forming（CAF） high cycle fatigue（HCF） microstructure 7075 aluminum alloy 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG146.15[金属学及工艺—金属材料]