Plasma-MIG复合电弧焊接特性分析  

Analysis on arc characteristics of plasma-MIG hybrid arc welding

作　　者：杨涛[1] 许可望[2] 刘永贞[2] 高洪明[1] 吴林[1] 

机构地区：[1]哈尔滨工业大学先进焊接与连接国家重点试验室,哈尔滨150001 [2]海洋石油工程股份有限公司,天津300452

出　　处：《焊接学报》2013年第5期62-66,116,共5页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(50974046);航天十二五科研项目

摘　　要：采用Plasma-MIG复合电弧对Q235低碳钢进行堆焊试验,对焊接过程中复合电弧形态、电弧空间分布、焊缝成形及细晶原理进行了分析.结果表明,Plasma-MIG复合电弧焊接过程中,外层等离子电弧单独存在,内层MIG电弧在焊丝端部与外层等离子弧耦合.复合电弧空间温度分布均匀,高温停留时间短,冷却速度快.Plasma-MIG复合电弧在大的等离子电流下,促进填充金属润湿铺展,焊缝熔宽大,成形美观.相同热输入量条件下,等离子电流增大能够促进晶粒自发形核,原奥氏体晶粒及焊缝组织得到细化.Bead welding experiment on Q235 mild steel plates with plasma-MIG hybrid arc was performed,and the space distribution of the arc,as well as the appearance and fine grain formation principle of the weld were discussed.The results show that the outer plasma arc is coupled with the inner MIG arc by the coactions on the filler metal tip during welding process.The temperature distributions in the arc space with the use of the hybrid arc are more uniform compared with that with the use of either one of the two arcs.The thermal cycle curve of the plates has a slightly high temperature span,indicating a fast cooling speed.With the increase of the plasma current in the hybrid arc,the wettability of the filler metal on the base metal and weld appearance are improved,and the weld width also increases.With the same heat input,the increase of the plasma current can improve the spontaneous nucleation of grains,thus the grains of the origin austenite and the weld are refined.

关 键 词：Plasma—MIG复合电弧 电弧形态 空间温度分布 细化晶粒 

分 类 号：TG434[金属学及工艺—焊接]