Removing the oxide film and dirt on the surface of the aluminium alloy can improve the welding quality of the aluminium alloy. In this paper, the characteristics of picosecond and 100 nanosecond pulsed laser cleaning aluminium alloys are explored by changing the average laser power, spot overlap ratio and scanning trajectory overlap rate. The results show that the oxide laser removal depth and diameter are related to the average power. As the average laser power increases, the depth and diameter of the ablation pit increase. At the same average power, the nanosecond laser ablation depth is greater than the picosecond laser. To achieve good surface quality, the nanosecond laser requires a higher overlap rate than the picosecond laser. The high overlap rate results in a nanosecond laser cleaning efficiency that is much lower than that of a picosecond laser. More importantly, the surface quality obtained by picosecond laser cleaning is much better than nanosecond laser cleaning. In addition, the welding experiment shows that the laser cleaning pre-treatment can effectively improve the welding quality.

去除铝合金表面的氧化膜和污垢可以提高铝合金的焊接质量。通过改变平均激光功率，光斑重叠率和扫描轨迹重叠率，研究了皮秒和100纳秒脉冲激光清洁铝合金的特性。结果表明，氧化物激光的去除深度和直径与平均功率有关。随着平均激光功率的增加，消融坑的深度和直径会增加。在相同的平均功率下，纳秒激光的烧蚀深度大于皮秒激光。为了获得良好的表面质量，纳秒激光器比皮秒激光器需要更高的重叠率。高的重叠率导致纳秒级的激光清洁效率远低于皮秒级的激光。更重要的是，通过皮秒激光清洗获得的表面质量比纳秒激光清洗要好得多。另外，焊接实验表明，激光清洗预处理可以有效提高焊接质量。