中厚板铝合金激光-MIG复合焊接工艺及组织性能  

Process and Microstructure Properties of Laser MIG Hybrid Welding for Medium-thick Aluminium Alloy Plate

作　　者：马国龙 马寅 李帅贞 杨志斌 韩晓辉 MA Guolong;MA Yin;LI Shuaizhen;YANG Zhibin;HAN Xiaohui(Technical Engineering Department,CRRC Qingdao Sifang Co.,Ltd.,Qingdao 266111,China;School of Material Science and Engineering,Dalian Jiaotong University,Dalian 116028,China)

机构地区：[1]中车青岛四方机车车辆股份有限公司技术工程部,山东青岛266111 [2]大连交通大学材料科学与工程学院,辽宁大连116028

出　　处：《电焊机》2024年第9期24-29,共6页Electric Welding Machine

基　　金：国家重点研发计划(2023YFB3407800)。

摘　　要：针对8 mm厚6005A-T6铝合金,分别采用I形坡口和Y形坡口进行激光-MIG复合焊接试验,通过对比研究不同坡口形式接头的焊缝成形、组织特征、硬度分布和拉伸性能,分析坡口形式对接头性能的影响规律。结果表明,两种坡口形式均能获得高质量的焊缝,但I形坡口焊缝的电弧主要作用区熔深更大。焊缝中心均为树枝状晶并且晶粒尺寸类似,与Y形坡口相比,I形坡口焊缝柱状晶区的宽度更大,且热影响区存在晶粒粗大的现象。I形坡口焊缝区和熔合线附近的硬度均低于Y形坡口,而热影响区的硬度高于Y形坡口。I形坡口和Y形坡口接头的平均抗拉强度分别为202.0 MPa和205.2 MPa,试样均断裂在熔合线附近,断裂路径与熔合线一致,断口呈现典型的塑性断裂特征。In this paper,laser-MIG hybrid welding experiments were carried out on the 8mm thick 6005A-T6 aluminum alloy.The weld formations,microstructures,microhardness distributions and tensile properties with different groove shapes were comparative studied.The results indicated that both I-shape and Y-shape grooves could obtain high quality welds,but the arc action zone penetration of I-shape groove was larger.The weld centers of I-shape and Y-shape grooves were dendritic and had similar grain size.Compared with Y-shape groove,the columnar crystal zone width of I-shape groove weld was larger than that of Y-shape groove,and the grain size in the heat-affected zone of I-shape groove weld was coarse.The microhardness values in the weld zone and near the fusion of I-groove shape were both lower than those of Y-shape groove,and the microhardness of heat-affected zone was higher than that of Y-shape groove.The average tensile strengths of I-shape and Y-shape joints were 202.0 MPa and 205.2 MPa,respectively.The samples fractured near the fusion line,and the fracture paths were consistent with the fusion line.The fracture showed typical plastic fracture features.

关 键 词：铝合金 激光-MIG复合焊 坡口形式 焊缝成形 组织性能 

分 类 号：TG456.7[金属学及工艺—焊接]