钢/铝管磁脉冲辅助半固态钎焊界面行为

结合电磁成形技术和半固态钎焊技术，提出了一种钢/铝管磁脉冲辅助半固态钎焊工艺，利用电磁脉冲产生的洛伦兹力使铝外管高速碰撞半固态钎料，通过半固态钎料中固相颗粒对母材表面径向压缩和轴向剪切作用去除母材表面氧化膜，实现钢铝异种管材的无钎剂钎焊. 在不同工艺参数下进行了钢/铝管磁脉冲半固态钎焊试验，研究了钎焊接头界面元素的扩散行为和金属间化合物的生长机理. 结果表明，焊缝组织主要为α-Al以及富锌相，铝侧界面处的Al₂O₃氧化膜破碎与去除情况良好，钢侧界面处有薄层FeAl₃金属间化合物形成，各部位均获得较好的冶金结合.

Interface behavior of steel/Al tube assisted semi-solid brazing by magnetic pulse

A semi-solid brazing process assisted by magnetic pulse for steel/aluminum tube was proposed by combining electromagnetic forming technology and semi-solid brazing technology. The brazing of steel and aluminum dissimilar pipes without flux soldering was realized by means of the radial compression and axial shear action of solid particles in the semi-solid solder to remove the oxide film on the surface of the base metal. The diffusion behavior of interface elements and the growth mechanism of intermetallic compounds in brazing joints were studied by magnetic pulse semi-solid brazing experiments of steel/aluminum tubes under different process parameters. The results show that the weld microstructure is mainly composed of α-Al and zinc-rich phase. The Al₂O₃ oxide film at the aluminum side interface is broken and removed well, and a thin layer of FeAl₃ intermetallic compound is formed at the steel side interface. Good metallurgical bonding is achieved at all parts.