焊接电流对镀铝锌钢板点焊接头质量的影响

Affect of Welding Current on Quality of Spot Welding Joints of Al-Zn Alloy Coated Steel Sheet

0.8mm镀铝锌钢板点焊时,影响其质量的主要焊接参数是焊接电流。本文在其它焊接参数不变的情况下,试验测试了焊接电流大小对接头质量的四个重要指标(即接头抗剪力、熔核直径、熔透率和表面压痕深度)的影响。结果表明,焊接电流小时,会产生未熔合或熔核尺寸太小,导致接头抗剪力低;电流太大时,造成飞溅,使表面压痕深度过大,致使镀层遭到破坏,降低接头的抗蚀性。适宜的焊接电流为7.5～9.0kA。

0.8 mm thickness Al-Zn alloy coated steel sheet spot welding, the impact on the quality of the main welding parameters are welding current. In this paper, other welding parameters remain unchanged, Test the welding current size of the joints of the four key indicators of quality（ie, joint shear strength, nugget diameter, penetration rate and the surface indentation depth）. The results show that the Welding current hours, will have no fusion or nugget size is too small, resulting in low shear joints; Current is too large, resulting in spatter, so that the surface indentation depth is too large, resulting in .the destruction of coatings to reduce the corrosion resistance of joints. Appropriate welding current for the 7.5-9.0 kA.