Abstract: In this paper, 5754 aluminum alloy with a plate thickness of 2 mm was selected, and by using fillet joint as the lap joint form, the laser fusion welding test was carried out. Taking the laser power P, welding speed v, and defocus Z as the experimental parameters, and the maximum tensile strength F of the welded joint as the response index, a mathematical model for response surface analysis was established. The results show that the laser power, welding speed, and defocus have obvious effects on the maximum tensile strength. The greater the laser power, the smaller the welding speed and defocus, the greater the maximum tensile strength. The established mathematical model was analyzed to determine the optimal process range, and combined with the macroscopic appearance of weld formation, the optimal process parameters were obtained. Compared with the optimal group in the test group, the maximum tensile strength was increased by 5.55%.
Keywords: 5754 aluminum alloy; response surface methodology; laser welding; process optimization; joint quality