镀锌钢板CMT铜钎焊焊接缺陷敏感性研究  

Study on weld defects sensitivity of CMT brazing galvanized steel sheets

作　　者：牟刚[1] 张跃龙[1] 华学明[1] 王大明 褚卫东 

机构地区：[1]上海交通大学材料科学与工程学院焊接工程研究所激光制造实验室,上海200240 [2]上海拖拉机内燃机有限公司,上海200433

出　　处：《电焊机》2017年第4期29-33,共5页Electric Welding Machine

摘　　要：针对汽车镀锌钢板CMT铜钎焊焊缝缺陷的敏感性问题,采用1.5 mm厚镀锌钢板搭接焊接的方法进行试验,主要以润湿性、焊接过程中是否存在飞溅、焊缝成形和镀锌层烧损情况作为评价铜钎焊焊接缺陷敏感性的指标,得到试验条件下缺陷敏感性较小时的工艺窗口:镀锌钢板搭接间隙为0~1 mm、电流为125~152 A时能获得合格的焊缝。通过改变点焊后不同气体保护时间确定焊缝表面变黑是由于焊缝在高温下被氧化生成氧化铜。Lap welding is operated with 1.5 mm thickness galvanized steel sheets to study the weld defect sensitivity of CMT brazing galvanized steel sheets for automobile. Four evaluation criteria are carried out to judge the weld defects sensitivity of brazing, which are wettability,spatters during weld process,weld geometry and burn-off of zinc deposits. And weld proeess window with few defects is obtained,that lap gap range is from 0 mm to 1 mm and current range is from 125 A to 152 A. Besides,through changing different shielding gas protection times after spot welding, a fact is confirmed that the dark substance on the brazing seam surface is due to the occurrence of CuO under high temperature.

关 键 词：CMT铜钎焊 镀锌钢板 缺陷敏感性 氧化 

分 类 号：TG457.1[金属学及工艺—焊接]