EH40钢摆动电弧窄间隙MAG焊接头粗晶区微观组织与性能  

Microstructures and mechanical properties of the coarse-grained region in welded joint of EH40 steel by swing arc narrow gap welding

作　　者：付魁军 倪志达 林三宝[2] 蔡笑宇 胡奉雅 Fu Kuijun;Ni Zhida;Lin Sanbao;Cai Xiaoyu;Hu Fengya(Ansteel Group Corporation,State Key Laboratory of Metal Material for Marine Equipment and Application,Anshan 114001,Liaoning,China;Harbin Institute of Technology,State Key Laboratory of Advanced Welding and Joining,Harbin 150001,China)

机构地区：[1]鞍钢集团公司,海洋装备用金属材料及其应用国家重点实验室,辽宁鞍山114001 [2]哈尔滨工业大学,先进焊接与连接国家重点实验室,哈尔滨150001

出　　处：《焊接》2020年第5期1-5,37,61,共7页Welding & Joining

基　　金：国家自然科学基金资助项目(51775139,51905128)。

摘　　要：采用2种焊接工艺参数对EH40微合金化钢进行摆动电弧窄间隙MAG焊,研究了填充厚度对热影响区粗晶区亚区分布的影响,并考察了焊接接头的力学性能。研究结果表明,摆动电弧窄间隙MAG焊适用于微合金化钢的窄间隙焊接,焊缝成形良好,未见未熔合等缺陷。填充厚度较大时,热影响区各亚区变化规律为未变再热粗晶区(UACG-HAZ)-过临界再热粗晶区(SCRCG-HAZ)-临界再热粗晶区(IRCG-HAZ)-粗晶区(CG-HAZ);填充厚度较小时,热影响区各亚区变化规律体现为SCRCG-HAZ到IRCG-HAZ。拉伸试样全部在母材处断裂,室温冲击吸收能量均能满足要求,摆动电弧窄间隙MAG焊工艺可以获得力学性能优良的EH40钢窄间隙MAG焊接头。Two welded joints of EH40 micro-alloyed steel were produced by narrow gap GMA welding with two welding parameters.The effect of filling thickness on the distribution of coarse-grained subregions in HAZ was analyzed and the mechanical properties of welded joints were studied.The research result showed that swing arc narrow gap MAG was suitable for narrow gap welding of microalloyed steel and good formation of weld was obtained without the defect,such as lack of fusion.Distribution of coarse-grained subregions was a periodic arrangement of UACG-HAZ,SCRCG-HAZ,IRCG-HAZ and CG-HAZ with a large filling thickness,while distribution of coarse-grained subregions was mainly a periodic arrangement of SCRCGHAZ and IRCGHAZ with a small filling thickness.All tensile specimens were broken at the base material,and the impact energy at room temperature could meet the requirements.The swing arc narrow gap MAG process could obtain MAG welded joint of EH40 steel with good mechanical properties.

关 键 词：摆动电弧 窄间隙焊接 微观组织 填充厚度 

分 类 号：TG444[金属学及工艺—焊接]