焊丝成分对汽车车身外观焊缝耐腐蚀性的影响

Influence of Chemical Composition of Welding Wires on Corrosion Performance of Joints on Exterior Surface of Car Body

通过研究不同焊丝MAG熔焊与CMT焊的碳钢接头的电泳和盐雾性能,分析焊丝化学成分对焊缝防腐性能的影响;并对比焊接接头力学性能,以保证接头质量满足白车身焊缝质量标准的前提下,提升汽车车身外观焊缝的防腐性能。结果表明,焊缝表面硅酸盐熔渣是导致电泳和盐雾性能恶化的主要原因。硅青铜焊丝CMT钎焊接头的力学和防腐综合性能比碳钢焊丝MAG熔焊接头的更佳,因此针对汽车车身外观面的接头焊接时,硅青铜焊丝可以取代碳钢焊丝。

The electrophoresis and salt spray properties of MAG welding and CMT welding carbon steel joints with different welding wires were studied, and the effect of chemical composition of welding wire on weld corrosion resistance was analyzed. The mechanical properties of welded joints were compared to ensure that the quality of welded joints meets the quality standards of white body welds, and the anti-corrosion properties of automobile body appearance welds are improved. The results show that silicate slag on weld surface is the main cause of deterioration of electrophoretic and salt spray properties. The comprehensive performance of mechanical and anti-corrosion of CMT brazing joints welded by silicon bronze welding wire is better than that of the MAG joints welded by carbon steel welding wires. Thus, the welding wire of silicon bronze can replace the carbon steel welding wire for the welding of joints on the exterior surface of car body.