汽车用镀锌板焊接缺陷控制研究进展
2021-09-13叶浩
叶浩



摘要: 简介了镀锌板在汽车行业的主要应用,介绍了镀锌板在汽车生产中常用的焊接工艺及其优缺点;主要综述了近几年来汽车镀锌板焊接缺陷控制的研究进展,有多种方法可以控制镀锌板焊接缺陷提高焊接接头质量,如预置镀锌板搭接间隙或预开锌蒸汽排气孔、优化焊接工艺参数、去除或减少焊缝镀锌层及调整填充焊丝的化学成分等,来减少焊缝气孔数量,提高焊接接头的质量。
关键词: CMT焊接; 激光焊接; 镀锌钢板; 焊接气孔; 焊接缺陷控制
中图分类号: TG 47
Research progress of welding defects control of galvanized steel for automobile
Ye Hao
(Fujian Benz Automotive Co., Ltd., Fuzhou 350119, Fujian, China)
Abstract: The main application of galvanized sheet in automobile industrywas briefly introduced in this paper, the common welding process of galvanized sheet in automobile production and its advantages and disadvantages were presented. The research progress of galvanized sheet welding defect control in automobile in recent years was reviewed. There were many ways to control the welding defects of galvanized sheet to improve the quality of welded joints, such as presetting the lap gap of galvanized sheet or preopening the steam vent of zinc, optimizing welding parameters, removing or reducing the galvanized layer of weld and adjusting the chemical composition of filling wire, so as to reduce the number of welding holes and improve the quality of welded joints.
Key words: CMT welding; laser welding; galvanized steel; welding porosities; welding defects control
0 前言
在当前汽车行业镀锌板已经广泛的代替传统的冷轧钢板,广泛的应用于白车身设计中。镀锌板目前的连接工艺主要有電阻点焊、熔化极混合气体保护焊(Metal active gas arc welding,MAG)、冷金属过渡焊接(Cold metal transfer welding, CMT)、激光焊接等。由于汽车生产过程中,存在零部件、半成品精度尺寸链累加情况,导致焊接过程存在焊缝精度、搭接间隙不稳定等问题,同时镀锌板焊接还存在锌蒸汽气孔问题,从而造成镀锌板焊接过程中容易产生焊偏、焊穿、气孔等品质缺陷。因此,如何更好的在镀锌板搭接焊中,对主要影响焊接品质的因素进行梳理,提供理论指导,为汽车生产过程中的品质管控提供参考,具有重大的意义。
1 镀锌板在汽车行业的应用
镀锌板是指在高强钢板表面通过电镀或热镀工艺,使其表面附着上双面锌金属薄层。镀锌层在高强钢板表面形成致密的保护层,形成物理防护[1],同时当镀锌层被破坏,内部钢板暴露时,外露的钢板和锌层会形成原电池,镀锌层作为牺牲阳极被氧化,而钢板作为阴极得到保护。……
