焊接电流对36Mn2V/45异种钢焊接接头组织和力学性能的影响  

Effects of Welding Current on Microstructure and Mechanical Properties of 36Mn2V/45 Dissimilar Steel Welded Joint

作　　者：许翠华 

机构地区：[1]中国煤炭科工集团西安研究院有限公司,陕西西安710065

出　　处：《热加工工艺》2017年第19期63-65,69,共4页Hot Working Technology

基　　金：陕西省火炬计划项目(S2016YFHJ0019)

摘　　要：采用CO_2气体保护焊焊接螺旋钻杆36Mn2V杆体和45钢叶片,运用宏观形貌、显微组织观察、显微硬度检测等方法研究了焊接电流对36Mn2V/45异种钢焊接接头微观组织和力学性能的影响。结果表明:随着焊接电流的增大,焊缝熔深与余高均增大,熔宽基本未变,焊缝成形系数减小。焊缝金属组织主要由侧板条铁素体、富碳马氏体、残余奥氏体以及弥散分布的粒状贝氏体组成。45钢侧粗晶区主要由马氏体和条状贝氏体组成。36Mn2V侧粗晶区主要由铁素体、马氏体及少量的粒状贝氏体组成。焊接电流较小时,焊缝金属和粗晶区的的组织较为细小均匀。接头热影响区和焊缝金属的显微硬度随着焊接电流的增大而降低。The welding of 36Mn2V rod and 45 steel blade was carried out by using CO2 gas shielded arc welding. The effects of welding current on the microstructure and mechanical properties of 36Mn2V/45 dissimilar steel welded joint were studied by observation of macroscopic morphology, microstructure and microhardness test, etc. The results show that with the increase of welding current, the weld penetration and reinforcement increase, the weld width does not change, and the weld forming factor decreases. The microstructure of weld metal mainly consists of side strip ferrite, carbon rich martensite, retained austenite and dispersively distributed granular bainite.The coarse grain region at side of 45 steel mainly consists of martensite and strip bainite, and that at side of 36Mn2V steel mainly consists of ferrite, martensite and a small amount of granular bainite. When the welding current is small, the microstrueture of weld metal and coarse grain region is fine and uniform. The microhardness of heat affected zone and weld metal of the welded joint decreases with the increase of welding current.

关 键 词：异种材料 钻杆 CO2气体保护焊 焊接电流 

分 类 号：TG444.73[金属学及工艺—焊接]