热处理对高速列车用7005铝合金焊接接头应力腐蚀敏感性的影响  

Effect of heat treatment on stress corrosion sensitivity of 7005 aluminum alloy welded joint for high-speed train

作　　者：张明鲲 杨敏 王宇 赵祥 井德强 Zhang Mingkun;Yang Min;Wang Yu;Zhao Xiang;Jing Deqiang(Xianyang Special Equipment Inspection Institute,Xianyang Shaanxi 712000,China;Shaanxi Special Equipment Inspection and Testing Institute,Xi'an Shaanxi 710000,China)

机构地区：[1]咸阳市特种设备检验所,陕西咸阳712000 [2]陕西省特种设备检验检测研究院,陕西西安710000

出　　处：《金属热处理》2023年第8期166-171,共6页Heat Treatment of Metals

基　　金：国家市场监督管理总局科技计划(2020MK103)。

摘　　要：采用慢应变速率拉伸试验,结合微观组织分析和断裂特征分析,研究了T6和回归再时效(RRA)热处理对7005铝合金焊接接头应力腐蚀敏感性的影响。结果表明,经T6及RRA热处理后,接头抗应力腐蚀开裂能力均得到提高,RRA热处理后接头的应力腐蚀敏感性指数显著降低,由焊态的0.37降低至0.05。RRA热处理接头的微观组织均匀,接头的抗拉强度和断后伸长率分别由焊态的329 MPa和6.8%提高至341 MPa和8.8%。因此RRA热处理可显著提高接头的力学性能和抗应力腐蚀开裂能力。Combined with microstructure analysis and fracture characteristics analysis,the effect of post-weld heat treatment of T6 and RRA on stress corrosion susceptibility of 7005 aluminum alloy welded joint was studied by means of slow strain rate tensile test.The results show that after T6 and RRA heat treatment,stress corrosion cracking resistance of the joint are improved,and the stress corrosion sensitivity index of RRA heat treated joints is significantly decreased from 0.37 as welded to 0.05.The microstructure of RRA heat treated joints is uniform,and the tensile strength and elongation after fracture of the joints increase from 329 MPa and 6.8%as welded to 341 MPa and 8.8%,respectively.Thus,RRA heat treatment can significantly improve the mechanical properties and stress corrosion cracking resistance of the joints.

关 键 词：7005铝合金 焊接接头 热处理 抗应力腐蚀 

分 类 号：TG441.8[金属学及工艺—焊接]