焊后固溶时效处理对6082-T6铝合金焊接接头组织和性能的影响  

Effect of solution aging treatment on microstructure and properties of 6082-T6 aluminum alloy MIG welded joints

作　　者：汪瀚清 王强[2] 王董琪琼 王素环 侯嘉鹏 李小武 张哲峰[2] WANG Han-qing;WANG Qiang;WANG Dong-qi-qiong;WANG Su-huan;HOU Jia-peng;LI Xiao-wu;ZHANG Zhe-feng(Department of Materials Physics and Chemistry,School of Materials Science and Engineering,Northeastern University,Shenyang 110819,China;Shi-changxu Innovation Center for Advanced Materials,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;Engineering Department of CRRC Sifang Co.,Ltd.,Qingdao 2661l1,China)

机构地区：[1]东北大学材料科学与工程学院材料物理与化学系,辽宁沈阳110819 [2]中国科学院金属研究所师昌绪先进材料创新中心,辽宁沈阳110016 [3]中车青岛四方机车车辆股份有限公司,山东青岛266111

出　　处：《轻合金加工技术》2022年第12期49-56,共8页Light Alloy Fabrication Technology

基　　金：中央高校基本科研业务专项资金资助(N2202003)。

摘　　要：试验研究了固溶时效处理对高速列车车体用6082-T6铝合金板材整体焊接接头组织和力学性能的影响机制。采用熔化极惰性气体保护焊(MIG)和ER6063铝合金焊丝对6082-T6铝合金板材进行焊接,采用金相显微镜、透射电镜观察焊接接头微观组织,采用拉伸机和硬度计测试焊接接头拉伸性能和显微硬度。试验结果表明,原始焊接接头抗拉强度约195 MPa;经固溶时效热处理后,母材和焊缝中析出纳米级强化相,焊接接头的整体力学性能得到改善,热影响区与母材显微硬度提升至122 HV,焊缝显微硬度提升至89 HV,焊接接头的抗拉强度高达320 MPa。在焊丝填充材料中引入Mg元素,在焊接接头整体固溶时效处理过程中与Si元素结合形成Mg_(2)Si强化相,显著改善了焊接接头的力学性能,实现了焊接接头的强韧化。This paper mainly studies the influencing mechanism of solid-solution aging treatment on the microstructure and mechanical properties of the overall welded joints of the 6082-T6 aluminum alloy sheet used for the high-speed train body.The 6082-T6 aluminum alloy sheet was welded by melt inert-gas(MIG)welding with ER6063 welding wire.The microstructure of the welded joint was characterized by Metallographic microscope and TEM,and the tensile properties and microhardness of the welded joints were examined with tensile machine and hardness tester.The experimental results show that the tensile strength of the original welded joint is 195 MPa.After a solid solution aging treatment,nano-precipitates are formed in the base metal and weld zone,and the integral mechanical properties of the welded joint are thus improved.The microhardness of heat affected zone and base metal is increased to 122 HV,the hardness of weld seam is increased to 89 HV,and the tensile strength of the welded joint reaches as high as 320 MPa.After introducing Mg into the filler material of the wire,the Mg element reacts with the Si element to form the strengthening phase of Mg_(2)Si during the overall solid solution aging treatment of the welded joint,and the mechanical properties of the welded joints are thus significantly improved,achieving the strengthening and toughening effect of the welded joint.

关 键 词：6082-T6铝合金 焊接接头 焊丝 MG2SI相 拉伸性能 

分 类 号：TG146.21[一般工业技术—材料科学与工程]