高端不锈钢轨道车辆激光叠焊技术开发与应用

Development and application of laser welding for high standard stainless steel railway vehicle

针对高端不锈钢地铁产品采用电阻点焊工艺出现外观水平低、效率低等问题,国内首创性开发出采用薄板搭接激光焊部分替代电阻点焊方法制造的不锈钢轨道车辆新产品。介绍了不锈钢车体激光搭接焊工艺开发,优化了工艺参数,得出在光斑直径为0.6 mm的前提下,激光功率1 200 W、焊接速度30 mm/s可获得剪切强度和下板外表面质量合格的接头。通过明确焊缝质量标准(熔深0.9 mm)并进行焊缝质量监测装置开发,搭建激光焊制造体系,实现了激光焊新技术在高端不锈钢轨道车辆产品中的批量化应用,激光焊不锈钢车体质量降低1.8 t,侧墙抗横向冲击性能显著提升,提升车体寿命15%以上。

In view of the problems of low appearance level and low efficiency in resistance spot welding of stainless steel rail vehicles, a new product of stainless steel rail vehicles is first developed in China, which is made by partially replacing resistance spot welding with laser welding of thin plates. The laser lap welding process of stainless steel car body is developed and the welding parameters are optimized. Under the condition of 0.6 mm spot diameter, the welded joint with qualified shear strength and quality of outer surface of lower plate can be obtained when the?laser power is 1 200 W and welding speed is 30 mm/s. By defining weld quality standard(0.9 mm penetration depth) and developing weld quality monitoring device, the laser welding manufacturing system is built, and the mass application of the new laser welding technology in high standard stainless steel rail vehicle products is realized. The weight of the stainless steel car body with laser welding reduces by 1.8 t, the lateral impact resistance of the side wall significantly improves, and the life of the car body increases by over 15%.