铝钢异种金属搅拌摩擦焊搭接接头组织与性能研究

Microstructure and property of friction-stir-welded lap joint of Al/Fe dissimilar alloys

通过对5052铝合金和Q235钢板搅拌摩擦搭接焊进行试验研究,获得质量良好的接头,通过剪切试验、断口形貌扫描电子显微镜和能谱分析对搭接接头组织和性能进行测试研究。结果表明:采用搅拌摩擦焊可以获得焊缝成形良好、无孔洞和裂纹等缺陷的搭接接头,强度可达到225 MPa,基本接近铝合金侧母材的强度,焊缝接头获得良好的机械连接和冶金连接。针对铝钢搭接的接头形式构建了组织模型,将接头分为搅拌扩散区、机械结合区和冶金结合区,揭示了铝钢搅拌摩擦搭接焊的连接机理。

Dissimilar metals of Al/Fe were lap-jointed by friction stir welding（FSW）,the properties and microstructure of the lap joint were studied. The results show that good appearance lap joint without defects,such as cavitation and crack,can be obtained by FSW,and the tensile strength of welded joints is 225 MPa,almost equal to that of Al base metal. The welded joint shows good mechanical and metallurgical bonding. The microstructure model of Al/Fe lap joint was built to reveal the joining mechanism of Al/Fe lap joint.