激光-MIG复合焊接中厚度不锈钢组织及性能研究  

Microstructure and Properties of Medium-Thick Stainless Steel by Laser-MIG Hybrid Welding

作　　者：陈志伟 马程远 陈波 檀财旺[1,2] 宋晓国 Chen Zhiwei;Ma Chengyuan;Chen Bo;Tan Caiwang;Song Xiaoguo(Shandong Key Laboratory of Special Welding Technology,Harbin Institute of Techmology(Weihai),Weihai,Shandong 264209,China;State Key Laboratory of Adanced Welding and Connection,Harbin Institute of Technology,Harbin,Heilongjiang 150001,China)

机构地区：[1]哈尔滨工业大学(威海)山东省特种焊接技术重点实验室,山东威海264209 [2]哈尔滨工业大学先进焊接与连接国家重点实验室,黑龙江哈尔滨150001

出　　处：《激光与光电子学进展》2020年第23期205-212,共8页Laser & Optoelectronics Progress

基　　金：国家重点研发计划(2018YFB1107900);山东省重点研发计划(2018GGX103026);山东省自然科学基金(ZR2017MEE042)。

摘　　要：采用激光焊与激光-MIG复合焊两种打底焊方式和激光-MIG复合焊与MIG(熔化极惰性气体)保护焊两种填充焊方式进行两两组合,完成了15 mm厚316L奥氏体不锈钢的焊接。对各试验组焊接接头的显微组织和力学性能进行了研究,结果表明,采用全激光-MIG复合焊得到的焊接接头成形最优。激光-MIG复合焊焊层中心部位存在胞状晶组织,而MIG焊焊层几乎全为柱状晶结构。复合焊填充层的拉伸强度高于MIG焊填充层,而激光打底层与复合打底层强度相当,所有断裂均为韧性断裂。两种打底焊层焊缝中心显微硬度均高于母材,复合填充焊层焊缝中心显微硬度略高于母材,MIG焊填充焊层则低于母材。The methods of underlying welding including laser welding and laser-MIG hybrid welding in combination with methods of filling welding including laser-MIG hybrid welding and MIG welding(melt inert-gas welding),are used to complete the welding of 15-mm-thick 316L austenitic stainless steel.The microstructure and mechanical properties of the weld joints in each group were studied.The results show that the weld joint obtained by all laser-MIG hybrid welding has the best formation.There is cellular structure in the center of laser-MIG hybrid welding layer,while the MIG welding layer is almost all columnar crystal structure.The tensile strength of the filling layer welded by hybrid welding is higher than that welded by MIG,while the strength of the underlying layer welded by laser is comparable to that welded by hybrid welding,and all fractures are ductile fractures.The micro-hardness of the weld center of the two different underlying layers is higher than that of the base metal,the micro-hardness of the weld center of the hybrid welding filling layer is slightly higher than that of the base metal,and the micro-hardness of MIG filling layer is lower than that of the base metal.

关 键 词：激光技术 激光电弧复合焊 中厚板不锈钢 显微组织 力学性能 

分 类 号：TG456.7[金属学及工艺—焊接]