Nanosecond pulse laser with different parameters was used to conduct laser cleaning experiments. Macroscopic and microscopic morphologies of the surfaces after laser cleaning were analyzed, and their properties were studied. The following conclusions were obtained. Macroscopic analysis of workpiece surface cleaning state shows that when the paint layer is insufficient or excessive cleaning, the cleaning degree can be roughly judged according to the change of surface color. The microstructure analysis of the workpiece surface cleaning state shows no burning trace on the paint surface when the workpiece surface cleaning is insufficient, and the surface elements are mainly C, O, and Si. Meanwhile, when the workpiece surface cleaning is moderate, the surface has visible microscopic oxide film cracks, and the surface elements are mainly Fe and O. Furthermore, the surface has an evident remelting phenomenon when the workpiece surface is overcleaned, and the surface elements are mainly Fe and O. The binarization processing results show that with an increase in cleaning degree, the number of white pixels in the image decreases, whereas the number of black pixels increases. Moreover, when the number of black and white pixels is almost the same, the cleaning is complete. According to this method, the surface quality after laser cleaning can be accurately evaluated. Our study provides an effective cleaning method and testing means for the surface paint film of the bogie wheel of high-speed rail.
Chunsheng Wang, Hongxiao Wang, Huiyan Xu, Guangzhong He, Kai Li, Xiaopeng Gu, Juan Dong. Quality Analysis and Online Evaluation of Axle Surface After Laser Cleaning[J]. Chinese Journal of Lasers, 2022, 49(8): 0802005