为了提高金属表面激光吸收率及激光微织构加工表面质量, 采用W-71s型喷枪在试样表面分别喷涂黑漆、水玻璃和黄料, 并用Nd∶YAG激光器对其进行激光微凹坑加工。与无涂层试样相比, 激光加工水玻璃和黄料涂层试样表面蚀除凹坑体积都增加, 其凹坑边缘熔渣体积都减少, 其中, 黄料涂层试样表面蚀除凹坑体积增加了29.4%; 在此基础上, 利用正交试验法探讨水玻璃和黄料的配比以及厚度对激光微织构加工表面蚀除凹坑体积和凹坑边缘熔渣体积的影响。结果表明, 吸光涂料的厚度控制在0.1mm左右, 黄料含量17%、水玻璃含量18%的涂料为最优涂料配方; 正交试验表中最优试样表面蚀除凹坑体积相比无涂层试样增加了70.6%, 其凹坑边缘熔渣体积减少了16.2%。该工艺显著提高了激光吸收率和激光加工表面质量。

In order to improve the laser absorption rate of metal surface and processing surface quality of laser micro-dimple,W-71s type spray gun was used to spray black paint, water glass and yellow material on the surface of samples, respectively. Then, the samples were processed by Nd∶YAG laser. Compared with the uncoated specimens, the dimple volume increased and slag volume decreased respectively, around the dimples of specimen surface coated with water glass and yellow material. Dimple volume of the sample coated with yellow material increased by 29.4%. On the basis, the influence of thickness and formula of water glass and yellow material on dimple volume and slag volume of laser processing surface were discussed by orthogonal experimental method. The results show that when the thickness of absorb light coating is about 0.1mm, the content of yellow material is 17% and the content of water glass is 18%, the coating formulation is optimal. Compared with the uncoated sample, dimple volume of the best sample in orthogonal table increased by 70.6% and the corresponding slag volume around the dimple decreased by 16.2%. The study indicates that laser absorption rate and laser processing quality on the surface can be significantly improved.