钢/铝异种金属激光填丝熔钎焊对接接头组织与性能分析  

Microstructure and Mechanical Property of Laser Wire Fusion Brazing Welded Butt Joints of Steel/Aluminum Dissimilar Metal

作　　者：高伟[1,2] 阎启 黄坚[1,2] 

机构地区：[1]宝钢集团汽车用钢开发与应用技术国家重点试验室,上海201900 [2]上海交通大学上海市激光制造与材料改性重点试验室,上海200240

出　　处：《中国激光》2014年第6期85-90,共6页Chinese Journal of Lasers

基　　金：汽车用钢开发与应用技术国家重点实验室2011年开放基金课题

摘　　要：采用光纤激光和铝硅焊丝对2.5mm厚6013铝合金和镀锌低碳钢的异种金属对接接头进行了激光填丝熔钎焊。采用光学显微镜、扫描电子显微镜(SEM)和能谱仪(EDS)分析了熔钎焊对接接头的微观组织,采用拉伸试验测试了接头强度,并研究了热输入对钢/焊缝界面处金属间化合物和接头强度的影响。试验结果表明,在适当焊接参数下可以获得成形良好和具有一定抗拉强度的钢/铝对接接头。进一步分析表明,钢/焊缝界面处主要生成了FeAl2和FeAl3金属间化合物。随着热输入量的增加,金属间化合物的厚度随之增加。焊缝中的组织则为α-Al基体晶界上均匀分布着条状Al-Si共晶组织。在钢板采用30°坡口时可以获得的最大抗拉强度为88MPa,采用45°坡口时强度可以达到135MPa。Dissimilar metal butt joints of 2.5 mm thick 6013 aluminum alloy and galvanized low carbon steel are welded by fiber laser wire fusion brazing method. The microstructure of the fusion brazing welded joints is investigated by optical microscope, scanning electron microscope （SEM） and energy dispersive spectrometer （EDS）. The joint strength is measured by tensile test. The effect of heat input on interface intermetallic compounds of aluminum/steel butt joint and joint strength are discussed. Experimental results show that butt joints with good appearance and certain tensile strength can be obtained under appropriate welding parameters. Further analysis reveal that this kinds of intermetallic compounds on the interface are mainly FeAl2 and FeAl3. With the increase of heat input, the thickness of the intermetallic compound is also increased. The uniform distribution of AI-Si eutectic along grain boundaries on α-Al substrate shows in welded seams. The maximum tensile strength of welded joints with a 30° groove is 88 MPa, the strength can reach up to 135 MPa when using a 45° groove.

关 键 词：光学制造 钢/铝异种金属 对接接头 激光填丝焊 熔钎焊 金属间化合物 

分 类 号：P755-1[天文地球—海洋科学]