本文以CuSi3为钎料,电镀锌钢板为母材,CO₂激光为热源,对卷对接接头进行了激光填丝钎焊研究.试验过程中,通过改变钎焊工艺参数及激光入射方式,研究了镀锌钢板激光填丝钎焊在不同热输入下的钎缝外观成形规律.结果表明,激光功率和光斑直径是影响钎缝成形最重要的因素;倾斜入射激光可以改善钎缝成形质量.此外,对不同热输入和同一接头不同部位的界面结合情况和界面元素的分布进行了SEM观察和电子探针分析.结果表明,随着钎焊线能量的增加,Si、Mn元素容易在界面处出现偏聚;相对于接头上部,接头下部钎料与母材结合微弱,界面更容易出现Si、Mn、Zn元素的富集.

Laser brazing of flanged joint of galvanized steel sheets was investigated in this paper, in which CuSi3 was used as brazing filler metal, the base metal was galvanized steel sheets and CO₂ laser was employed as heating source. In experiments, brazing parameters and laser incident angle were changed during the process. The regularity of appearance of brazing seam in different heat input was obtained. The experimental results indicated that laser power and spot diameter are the important factors for a good appearance of brazing seam and the inclination of the incident laser beam is useful for the wetting and spreading of the filler metal. Moreover, SEM and electron microprobe scanning analysis of the joints were carried out. The investigation indicated that the joint combined condition and the distribution of active elements Si, Mn and Zn at the interface of different joints and different parts of the same joint are related to the heat input and the position in the joint closely.