HR550LA+Z汽车用镀锌高强钢板GMAW工艺研究  

Study on GMAW Procees of HR550LA+Z Galvanized High Strength Steel Plate for Automobile

作　　者：刘北辰 李芳[1,2] 王成龙 金鑫 华学明[1,2] 

机构地区：[1]上海交通大学上海市激光制造及材料表面改性重点实验室,上海200240 [2]高新船舶与深海开发装备协同创新中心,上海200240 [3]上海汇众汽车制造有限公司,上海200433

出　　处：《热加工工艺》2018年第1期57-61,共5页Hot Working Technology

摘　　要：采用脉冲、CMT和短路三种不同的电流模式进行了HR550LA＋Z汽车用镀锌高强钢板的对接焊接试验,得到了不同电流模式的焊接工艺窗口,并分析了焊接接头的组织。结果表明,焊接电流模式对焊接接头组织影响不大,焊缝区组织为针状铁素体和粒状贝氏体,粗晶区组织为80～100μm大小的板条马氏体和少量粒状贝氏体;细晶区组织为20μm左右的粒状贝氏体和少量铁素体。不同电流模式下工艺窗口有明显差异。对于2.4 mm的HR550LA＋Z对接接头,短路模式的焊接速度较低,高焊接速度下容易出现大颗粒飞溅;CMT模式下需较高电流才足以将板焊透,但高电流易造成镀锌层的烧损;脉冲焊的工艺窗口宽,电流范围为100～160 A,焊接速度范围为55～125 cm/min。脉冲电流模式更适合应用于2.4 mm的HR550LA＋Z镀锌钢板的焊接。The butt welding tests of HR550LA＋Z galvanized high strength steel plate for automobile were carried out by using the three different current modes of pulse, CMT and short circuit. The welding process windows with different current modes were obtained, and the microstructure of welded joints was analyzed. The results show that the welding current mode has little effect on the microstructure of welded joints. The microstructure of the weld zone is acicular ferrite and granular bainite ,the microstructure of the coarse grain zone is lath martensite with size of 80-100 μm and a small amount of granular bainite, and the microstructure of the fine grain zone is granular bainite with size about 20 μm and a small amount of ferrite. There are obvious differences in the process windows under different current modes. For 2.4 mm HR550LA＋Z butt joint, the welding speed under short circuit mode is low, and it is prone to produce large particle spatter under high welding speed. High current required to weld the plate under CMT mode, but high current is easy to cause the burning of galvanized layer. The pulsecurren welding process window is wide and the current range is 100-160 A, and the welding speed range is 55-125 cm/min. Pulsed current mode is more suitable for the welding of 2.4 mm HR550LA＋Z galvanized steel plate.

关 键 词：HR550LA+Z 镀锌高强钢 熔化极气体保护焊 脉冲电流 冷金属过渡 短路焊 

分 类 号：TG444.2[金属学及工艺—焊接]