不锈钢板激光光束摆动叠焊工艺研究

采用光纤激光器和D50摆动激光头进行不锈钢板激光叠焊工艺研究，分析了5种激光光束摆动方式对焊缝成形和气孔率的影响规律，并对直线形光束摆动方式下的焊接工艺参数进行了优化。研究结果表明：相对于常规激光焊接，5种激光光束摆动方式焊接均能有效增大叠焊板结合面熔宽，并可抑制焊缝气孔的产生。在直线形光束摆动方式下，随着激光功率增大或焊接速度减小，焊缝熔深和结合面宽度均增大；随着摆动频率增大，熔深则相应减小；随着摆动振幅增大，焊缝截面形状由丁字形向椭圆形、梯形转变。当激光功率、焊接速度、离焦量、摆动振幅和摆动频率分别为3 kW、2.4 m/min、5 mm、1.5 mm和300 Hz时可获得成形好、气孔较少、剪切强度较高的叠焊接头。

Research on Laser Beam Wobble Lap Welding Processes of Stainless Steel Sheets

The lap welding processes of stainless steel sheets were studied by using fiber laser assembled with D50 wobble laser head, the influences of five laser beam wobble types on weld formations and porosities were analyzed, and the welding process parameters were optimized under the linear beam wobble mode. The research results show that compared with conventional laser welding, the five types of laser beam wobble welding may effectively increase the interface fusion width in the lap joints, and may inhibit the weld porosity. Under the linear beam wobble mode, both of the weld penetration and interface fusion widths increase with increasing welding powers or reducing welding speeds, the weld penetration decreases with increasing wobble frequencies. With the increasing of wobble amplitude, the cross section shapes of lap welding joints change from T-shaped, oval-shape to trapezoid-shape. A good lap welding joint with low porosity and high shear strength may be obtained under the parameters where the laser power, welding speed, defocusing distance, wobble amplitude and wobble frequency are as 3 kW, 2.4 m/min, 5 mm, 1.5 mm and 300 Hz respectively.