摘要
针对高强不锈钢车体常用的301L不锈钢搭接接头,采用不同光斑直径光纤激光器和焊接工艺参数,进行激光非熔透焊接工艺研究,获得了激光焊接工艺参数对焊缝成形质量、表面热影响痕迹、焊缝熔化形状和接头拉剪性能的影响规律,并对激光焊接工艺参数的优化原则和方法进行了讨论。结果表明,对于0.8mm内板(301L-H)和1.5mm外板(301L-1.4318)组合,当激光聚焦光斑直径不小于0.4mm且功率大于2kW时,能在较大的参数窗口内确保搭接接头外观和力学性能满足要求;对于光斑直径为0.4mm的光纤激光器,为确保无热影响区痕迹,应精确控制熔深小于1.4mm,为确保拉剪性能大于等价电阻焊接头,结合面熔宽应大于0.8mm;对于母材强度高于930MPa的301L-H不锈钢板搭接接头,剪切拉伸断裂位置始终位于内外板结合面的焊缝处,接头承载能力与结合面熔宽线性相关。
Partial penetration lap laser welding was used for 301 L-H stainless stesolve the heats and the weld distortion problems. The effects of focused laser spot diameter and weld-ing parameters were investigated with using fiber laser. Relationship among processing parameters and welding quality index like formation quality, heat trace on the surface, penetration shape and sheartensile performance,were concluded. The principles and methods were discussed for the selection of optimized parameters. For the combination of 0.8 mm and 1.5 mm high tensile strength plates,which were typically used for light weight train bodies,the outputs of laser machine should be over 2 kW, and the focused spot diameters should be over 0.4 mm if a large processing window was obtained to satisfy both appearance and mechanical requirements. For fiber laser with 0.4 mm spot diameter,the penetration should be less than 1.4 mm to make the outside surfaces no heat traces, and the fusion width in the interfaces between inner and external plate should be more than 0.8 mm to make the ten-sile strength higher than that of resistance spot welding. For 301 L-H stainless steel with tensile strength over 930MPa,the fractures are always located in the fusion zones at the interfaces between inner and externalplates,so the tensile capacity is linearly related to the fusion widths in the interfaces.
出处
《中国机械工程》
EI
CAS
CSCD
北大核心
2017年第11期1355-1361,共7页
China Mechanical Engineering
基金
国家自然科学基金资助项目(U1537205)
关键词
不锈钢
激光焊接
搭接
轨道交通
stainless steel
laser welding
lap joint
railway transport
