利用兆赫兹量级高重复频率皮秒激光对304不锈钢进行烧蚀，通过激光共聚焦显微镜和扫描电子显微镜对烧蚀表面进行测量观察。结果表明：单脉冲峰值能量密度和重复频率共同决定不锈钢的烧蚀率，单脉冲峰值能量密度与烧蚀阈值比值越大，烧蚀率越大；在高频低峰值能量密度下能获得更优的表面烧蚀质量。随着扫描速度的提高，烧蚀深度呈对数函数关系逐渐减小，烧蚀后的表面粗糙度先减小后趋于稳定。扫描速度在1.0~1.7 m/s内变化时，烧蚀率变化不大。因此采用交叉扫描路径有利于提高烧蚀后的表面质量。

A picosecond laser with a high repetition rate of MHz is used to ablate stainless steel 304 and the surface after ablation is observed and measured by laser scanning confocal microscope (LSCM) and scanning electron microscope (SEM). The results show that the ablation rate is jointly determined by the single pulse peak fluence and the repetition rate. The ablation rate increases as the ratio of pulse peak fluence to ablation threshold increases. Better ablation quality of surfaces can be achieved under the conditions of lower peak fluence and higher repetition rate. With the increment of scanning speed, the ablation depth decreases logarithmically, and the roughness degree of ablation surface decreases first and then stabilizes. When the scanning speed is between 1.0 m/s and 1.7 m/s, the ablation rate shows no obvious change. The use of cross scanning path is beneficial for improving the surface quality after ablation.