高速列车铝合金横梁构件激光-MIG复合焊与MIG焊焊接特性对比研究  

Comparative Study on Welding Characteristics of Laser-MIG Hybrid Welding and MIG Welding for Aluminum-Alloy Crossbeam Components of High-Speed Train

作　　者：杨志斌 盛立康 谢延祺 Yang Zhibin;Sheng Likang;Xie Yanqi(School of Materials Science and Engineering,Dalian Jiaotong University,Dalian 116028,Liaoning,China)

机构地区：[1]大连交通大学材料科学与工程学院,辽宁大连116028

出　　处：《激光与光电子学进展》2024年第21期256-262,共7页Laser & Optoelectronics Progress

基　　金：辽宁省教育厅科学研究基金(JDL2020026)。

摘　　要：针对高速列车铝合金横梁构件分别开展激光-熔化极惰性气体(MIG)复合焊和MIG焊试验,对比研究两种焊接方法的焊缝成形、微观组织和力学性能。结果表明:两种焊接方法均可获得成形质量良好的焊缝,相比MIG焊,激光-MIG复合焊的效率提升约8倍、线能量降低约70%。两种焊接方法焊缝中心均为树枝状晶,相比MIG焊,激光-MIG复合焊熔合线焊缝侧为柱状晶组织且熔合区不明显。激光-MIG复合焊焊缝中心硬度略高于MIG焊,激光-MIG复合焊最低硬度位于熔合线附近,MIG焊最低硬度位于焊缝区域。激光-MIG复合焊和MIG焊接头的抗拉强度分别为218.7 MPa和177.0 MPa,试样分别断裂在熔合线附近和焊缝区,均表现为塑性断裂特征。In this study,laser-MIG hybrid welding and MIG welding were performed on aluminum-alloy crossbeam components of high-speed trains.Additionally,the weld formation as well as the microstructure and mechanical properties of the two welding methods were compared and investigated.The results show that both welding methods can achieve welds with good forming quality.Compared with MIG welding,laser-MIG hybrid welding offers a higher efficiency by approximately eight times while reducing the line energy by approximately 70%.The weld center of the two welding methods is a dendritic crystal.Compared with MIG welding,the laser-MIG hybrid welding features a columnar crystal in the fusion line at the weld side and the fusion zone is ambiguous.The hardness of the weld center resulting from laser-MIG hybrid welding is slightly higher than that from MIG welding.The lowest hardness achieved by laser-MIG hybrid welding is near the fusion line,whereas that achieved by MIG welding is in the weld area.The tensile strength of joints resulting from laser-MIG hybrid welding and MIG welding are 218.7 MPa and 177.0 MPa,respectively.The tensile specimens are fractured near the fusion line and weld zone,respectively,and both present the typical plastic fracture.

关 键 词：激光技术 激光-熔化极惰性气体复合焊接 熔化极惰性气体保护焊 铝合金 组织性能 

分 类 号：TG456.7[金属学及工艺—焊接]