6061铝合金焊后氧化物的激光清洗机理和工艺研究

Research on Laser Cleaning Mechanism and Process of Oxides After Welding of 6061 Aluminum Alloy

采用纳秒脉冲激光器对6061铝合金焊后氧化物进行激光清洗实验。首先分析焊斑清洗前和清洗后的表面形貌和元素组成,探明焊后氧化物组成成分。其次再利用前期实验所获得不同工艺参数对清洗质量的影响规律,设计正交实验,划定各因素区间范围,分析参数对清洗质量的影响权重。利用正交实验法分析得到:影响表面轮廓线峰谷值的参数主次顺序为激光功率>脉冲频率>扫描速度>脉冲宽度;影响氧元素质量百分比的参数主次顺序为脉冲宽度>扫描速度>激光功率>脉冲频率。通过综合平衡法最终获得优化工艺参数组:扫描速度、激光功率、脉冲频率、脉冲宽度分别为2950 mm/s、141 W、29 kHz、330 ns。优化后可确保铝合金焊后氧化物清洗彻底、无基材损伤、清洗效率高。

A nanosecond pulse laser is used to conduct laser cleaning experiments on the oxide after welding of 6061 aluminum alloy.Firstly,This paper analyzes the surface morphology and elemental composition of the solder joint before and after cleaning,and determines the composition of the oxide after welding.Secondly,based on the influence of different process parameters on cleaning quality obtained from previous experiments,orthogonal experiments are designed to delineate the range of each factor interval and analyze the weight of the influence of parameters on cleaning quality.By using the orthogonal experimental method,it is found that the order of parameters affecting the peak valley values of surface contour lines is:Laser power>pulse frequency>scanning speed>pulse width.The order of parameters that affect the weight percentage of o element is:Pulse width>scanning speed>laser power>pulse frequency.The optimal process parameter group is obtained through the comprehensive balance method:Scanning speed,laser power,pulse frequency,and pulse width are 2950 mm/s,141 W,29 kHz,and 330 ns,respectively.The optimal parameters can ensure thorough oxide cleaning,no substrate damage,and high cleaning efficiency of aluminum alloy after welding.