采用平均功率为2KW的光纤耦合输出Nd:YAG固体激光器, 对焊缝长度为1m, 厚度为2mm的5052铝合金进行脉冲激光自熔拼焊, 分析了激光功率、激光频率、焊接速度、离焦量、入射角、气体保护方式等工艺参数对焊接质量的影响, 研制出大幅面激光拼焊的专用夹具。找出了一定厚度的5052铝合金大幅面拼焊的最佳工艺参数。并对焊接接头的显微组织和力学性能进行了研究。结果表明, 当激光平均功率为2KW; 峰值功率为3.9KW; 激光输出方形脉冲频率为260Hz; 占空比为45.2%; 焊接速度为2m/min; 离焦量为-0.6mm; 正反面以15°侧吹保护高纯氩气流量为10L/min; 透射聚焦透镜焦距为160mm时, 焊接接头整体力学性能优良, 其拉伸强度达到母材的80%以上。

The effects on laser welding quality have been analyzed due to laser technical parameters such as laser power, laser frequency, welding speed, focus position and so on, based on the laser welding large sheet(length：1m; thickness：2mm)aluminum-alloy 5052 experiment, Using 2KW solid-state laser with fiber output system and a special sort of fixture. At the same time, the microstructures and properties of butt laser joints of aluminum alloy 5052 sheets have been studied. The results show that the mechanical property of the joint is good, tensile strength is up to 93% of the base metal at the conditions of laser average power 2KW, laser peak power 3.9KW, laser square pulse frequency 260Hz, laser duty 45.2%, welding speed 2m/min, focus length 160 mm.