为了得到高质量的钢/铝接头, 采用激光摆动焊接的方法、使用不同的功率对DP780双相钢和5083铝合金两种金属进行了搭接实验, 研究了不同焊接功率对钢/铝接头宏观形貌、微观组织和力学性能的影响。结果表明, 1400W~1600W的功率区间内可有效实现板材焊接; 激光功率为1400W和1500W时, 焊接接头的金相组织以马氏体为主, 当激光功率为1600W时, 接头内的铁素体增多, 马氏体减少, 焊接接头的金相组织以铁素体为主; 3种接头显微硬度的最低值和最高值分别位于焊缝中心和热影响区, 在1500W的激光功率下, 焊接接头的力学性能最好, 钢侧接头的显微硬度约高于母材显微硬度的1.7倍; 接头的最大剪切强度达到113N/mm。此研究结果应用在船舶制造领域具有较重要的意义。

In order to obtain high quality steel/aluminum joints, the lapping experiments of DP780 duplex steel and 5083 aluminum alloy with different power were carried out by laser swing welding. The effects of different welding power on the macroscopic morphology, microstructure, and mechanical properties of steel/aluminum joints were investigated. The test results show that the plate welding can be effectively realized within the power range of 1400W~1600W. When the laser power is 1400W and 1500W, the metallographic structure of the welded joint is dominated by martensite. When the laser power is 1600W, the amount of ferrite in the joint increases, while the martensite decreases, and the metallographic structure of the welded joint is dominated by ferrite. The lowest and highest microhardness of the three joints were located in the weld zone and the heat affected zone, respectively. Under the laser power of 1500W, the mechanical properties of the welded joint are the best, and the microhardness of the steel side joint is about 1.7 times higher than that of the base metal. The maximum shear strength of the joint is 113N/mm. The research results are of great significance in the field of shipbuilding.