As a lightweight material, the high-silicon aluminum alloy Al-25Si-4Cu-Mg has been widely used in aerospace, transportation and construction. Porosity is the most common welding defect in laser welding of high silicon aluminum alloy, and has a certain impact on the properties of high-silicon aluminum alloy. A comparative study of the continuous laser welding (CLW) and pulse laser welding (PLW) of Al-25Si-4Cu-Mg must be conducted to explore the influence of different laser energy output modes on welding. The TruPulse556 pulse lasers and IPG continuous lasers were used to perform the laser welding test in this study. Moreover, a comparative analysis of the PLW and CLW of Al-25Si-4Cu-Mg in terms of microstructure and mechanical properties, including the weld microstructure, hardness, the tensile properties, and porosity. The research shows that PLW inhibits the formation of porosity more effectively than CLW. The mechanical properties and microstructure of the Al-25Si-4Cu-Mg welded joint can be improved by PLW, which has significance to the research on the PLW of high-silicon aluminum alloy.

高硅铝合金Al-25Si-4Cu-Mg作为一种轻量化材料，已广泛应用于航空航天、交通运输和建筑等领域。气孔是高硅铝合金激光焊接中最常见的焊接缺陷，对高硅铝合金的性能有一定的影响。必须对 Al-25Si-4Cu-Mg 的连续激光焊接 (CLW) 和脉冲激光焊接 (PLW) 进行比较研究，以探讨不同激光能量输出模式对焊接的影响。本研究中使用 TruPulse556 脉冲激光器和 IPG 连续激光器进行激光焊接测试。此外，还对 Al-25Si-4Cu-Mg 的 PLW 和 CLW 在微观结构和力学性能方面进行了比较分析，包括焊缝微观结构、硬度、拉伸性能和孔隙率。研究表明，PLW 比 CLW 更有效地抑制孔隙的形成。PLW可以改善Al-25Si-4Cu-Mg焊接接头的力学性能和显微组织，对高硅铝合金PLW的研究具有重要意义。