钢-铝激光焊接的关键技术与未来趋势展望

The Key Technology and Future Tendency of Laser Welding of Steel-Aluminum

汽车车身多材料结构要求两种不同类型的材料进行连接(如钢-铝、铸铁-铝、铝-镁等)。激光焊热量集中,热源能准确控制,应力应变小,与其他焊接方法相比,更适合于钢、铝异种材料的焊接。在分析钢-铝焊接难点的基础上,总结了当前钢-铝激光焊接中常见的焊接缺陷、接头连接形式、表面处理及填加焊料,着重概括了激光焊接工艺参数对焊缝质量的影响,指出钢-铝激光焊接技术未来的发展趋势是设计与开发柔性化夹具,加强钢-铝激光焊接工艺参数优化、焊接缺陷控制、合金元素填料筛选、FeAl脆性金属间化合物与延塑性较好金属间化合物的形成条件、Fe/Al界面结合机理等方面的基础研究,期望为激光焊接多材料车身结构提供重要的技术参考。

Two different types of materials like steel and aluminum, cast iron and aluminum, magnesium and aluminum are joined each other to meet the requirement of multi-materials vehicle body. Compared with other welding means, laser welding is more suitable to weld steel to aluminum due to its characteristic of concentrated power, accu racy of controling heat source, low strain and stress. Based on analyzing the difficulties of welding steel and alumi- num, some common current defect, forms of joint, surface treating and filler of welding steel and aluminum are sum- marized and the influence of laser welding parameters is emphasized. As a developing trend, to design and develop a flexible jacket, to reinforce the optimization of laser welding parameters, to control welding defects, to select proper filler, to do research on the mechanism of integrating Fe-Al interface and the condition of forming brittle and ductile intermetallic FeAl compound are also pointed out in order to provide reference for welding multi-materials vehicle body.