Investigation on microstructure and fatigue behavior of Al-5Zn-2Mg high strength aluminum alloy with T5 heat treatment
The low cycle fatigue property of Al-5Zn-2Mg high strength aluminum alloy with T5 heat treatment was tested, and the fatigue damage behaviors were observed by OM, SEM and TEM. The results show that the rolling direction of Al-5Zn-2Mg high strength aluminum alloy is distinct. The separations, such as inclusions, mostly distribute along the rolling direction. The η (MgZn2) transitional strengthening phases are precipitated in Al-5Zn-2Mg aluminum alloy, and mostly distributed in grain boundary. The appearance of strengthening phase is ellipsoid. Its diameter of short axis is about 20nm, and the diameter of long axis is about 40nm. The cycle fatigue life is 4.22×106 cycle in R=0.1, f=8Hz, and σmax=127-210MPa. The fatigue crack initiates in surface of Al-5Zn-2Mg aluminum alloy sample, while the fatigue crack come into being and propagate along the rolling direction. The fatigue stress causes the loose microstructure. There have the fatigue striations and shell texture in fatigue crack propagation zone.
high strength aluminum alloy microstructure fatigue damage
Yang Shanglei Xu Chao Lin Qinlin Ding Bo
School of Materials Engineering, Shanghai University of Engineering Science, Shanghai 201620, China Technology Center, CSR, Sifang Locomotive and Rolling Stock Co., Ltd. Qingdao 266111, China
国际会议
北京
英文
151-154
2012-10-23（万方平台首次上网日期，不代表论文的发表时间）