X80/X100异种钢激光-MIG复合焊接头显微组织和性能  

Microstructure and properties of laser-MIG hybrid welded X80 and X100 steel dissimilar joint

作　　者：严春妍[1] 姜心怡 周倩雯 张可召 赵立娟[1] 王宝森[2] YAN Chunyan;JIANG Xinyi;ZHOU Qianwen;ZHANG Kezhao;ZHAO Lijuan;WANG Baosen(Hohai University,Changzhou 213022,China;Baosteel Central Research Institute,Shanghai 200431,China)

机构地区：[1]河海大学,常州213022 [2]宝钢集团中央研究院,上海200431

出　　处：《焊接学报》2023年第1期20-26,I0003,I0004,共9页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51804097);江苏省研究生科研创新计划(KYCX21_0470)。

摘　　要：采用激光-MIG复合焊对X80管线钢和X100管线钢进行焊接,研究了激光功率对复合焊接头的焊缝形貌、显微组织、硬度、强度和韧性的影响规律.结果表明,激光功率从2.0 k W增大至3.5 k W时,盖面焊缝熔宽和熔深增加,激光区熔深明显增加;激光区焊缝中AF含量增加、LB含量减少,X100侧粗晶热影响区和细晶热影响区中条状贝氏体含量减少,X80侧粗晶热影响区和细晶热影响区中准多边形铁素体含量增加.复合焊接头硬度分布并不对称,最高硬度出现在X100侧熔合区部位.复合焊接头的抗拉强度基本不随激光功率变化,拉伸试样断裂位置均为X80侧母材.随着激光功率增大,焊接接头最高硬度和韧性均下降.X80 and X100 pipeline steels were welded together by laser-MIG hybrid welding method.The effects of laser power on weld geometry,microstructures,hardness,tensile strength and impact toughness of the hybrid welded joints were investigated.Results show that,when laser power is elevated from 2.0 kW to 3.5 kW,both weld bead width and penetration of cap weld increase with a pronounced rise in laser zone penetration.Increasing acicular ferrite content and decreasing lath bainite content is obtained in the laser zone weld.The contents of lath bainite in coarse grained heat affected zone and fine grained heat affected zone of X100 steel side decrease.The contents of quasi-polygonal ferrite in coarse grained heat affected zone and fine grained heat affected zone of X80 steel side increase.Hardness distribution is asymmetrical with the maximum hardness occurs in the fusion zone.Tensile strength of the hybrid welded joints barely changes with varying laser powers,and all the tensile specimens fractured at base metal of X80 steel side.Maximum hardness and impact toughness of the hybrid welded joint decrease with increasing laser power.

关 键 词：激光电弧复合焊 异种钢 力学性能 显微组织 

分 类 号：TG456.7[金属学及工艺—焊接]