点焊镀锌钢板的电刷镀电极的微观结构与点焊工艺

Effect of brushing Co of electrodes on performance of spot welding process of zinc coated steel sheets

为了改善镀锌钢板点焊工艺 ,在点焊电极端面电刷镀了金属材料Co ,用该电极进行了镀锌钢板点焊工艺实验 ,观测了电极电刷镀前后镀锌钢板点焊焊点表面质量 ,用扫描镜观测了电刷镀层与电极基体结合面的微观结构和焊后电极端面的元素分布及焊点表面元素的分布。分析了Co电刷镀层改善镀锌钢板点焊工艺的原因。实验结果表明 ,在镀锌钢板点焊电极端面电刷镀一层Co可抑制飞溅、避免粘电极 ,从而改善了镀锌钢板点焊工艺性 ;在点焊电极端面电刷镀一层Co可以阻止点焊过程中铜锌合金层的形成 ;电刷镀层与电极基体的结合强度满足镀锌钢板点焊的工作要求。

To improve the performance of spot welding process of zinc coated steel sheets, spot welding electrodes are brushed with metal Co on the surfaces of them. Spot welding experiments are carried out with the electrodes.The surface qualities of the electrodes before and after brushing are observed.The microstructures of the interface layer between the plating layer and the base of the electrodes are observed. At the same time, the distributions of elements in the surfaces of the electrodes and the welds are detected out. Experimental results show that Co brushed on the surfaces of electrodes can prevent from splashing,avoid electrodes sticking and improve the performance of spot welding process of zinc coated steel sheets. The reasons why it can improve the performance of spot welding are analyzed. In a word, the layer of metal Co can keep Cu and Zn from alloying and the joining strength can satisfy the requirement of the spot welding process of zinc coated steel sheets.