中文摘要：

针对激光在硬脆性材料精密加工中存在比较严重的再铸层和不可避免的微裂纹、热变形等影响激光加工表面质量现象，利用低压水射流辅助激光加工的方法对W6M05Cr4V2高速钢进行试验加工，对比分析了激光加工参数对常规激光加工与低压射流辅助激光加工后的材料表面微观形貌的影响，研究了激光加工参数对常规激光加工与低压射流辅助激光加工热影响区的影响规律。研究结果表明：这种利用射流束的冲蚀作用的复合加工方法对高速钢加工的表面质量有非常显著的改善作用，复合加工后的高速钢材料表面无明显的再铸层。同时，由于射流束的冷却作用，相对于常规激光加工来讲，复合加工后的高速钢材料表面热影响区显著减小。

英文摘要：

Recast layer, micro cracks and thermal deformation limited the improvement of the surface quality of laser processing in precision machining of hard and brittle material. Thus, a process named as Low-pressure Water jet Assisted Laser Processing is presented in this paper. A comprehensive study on the influence of laser processing parameters on surface quality of WrMo5Cr4V2 high-speed steel is presented. The surface quality of normal laser processing and low-pressure water jet assisted laser processing is comparative analyzed, and the influences of laser processing parameters on heat affected zone are analyzed too. The results show that the composite processing of low-pressure water jet assisted laser processing can obtain good surface quality, slight moltenslag and recast layer ,compared with the normal laser processing. At the same time, the heat affected zone is significantly reduced.