Effects of Aging Temperature on Microstructure and High Cycle Fatigue Performance of 7075 Aluminum Alloy
来源期刊:Journal Of Wuhan University Of Technology Materials Science Edition2017年第3期
论文作者:杨大炼 刘义伦 LI Songbai MA Liyong LIU Chi YI Jiuhuo
文章页码:677 - 684
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.
杨大炼1,2,刘义伦2,3,LI Songbai2,MA Liyong4,LIU Chi2,YI Jiuhuo2
1. Hunan Provincial Key Laboratory of Health Maintenance for Mechanical Equipment, Hunan University of Science and Technology2. School of Mechanical and Electrical Engineering, Central South University3. Light Alloy Research Institute, Central South University4. School of Mechanical Engineering, Hebei University of Architecture
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.
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