Abstract Owing to high hardness and high brittleness of SiC ceramic, it is difficult to machine into structural ceramic components with desired surface quality and dimensional accuracy. In this paper, a method of polishing SiC ceramic by underwater femtosecond laser was proposed. The influence of laser frequency and pulse energy on surface morphologies, 3 D profiles, depth and surface roughness of polished SiC ceramics during underwater femtosecond laser processing was investigated in detail. The experimental results indicated that the removal depth during underwater polishing increased and then decreased with the increase of laser frequency and pulse energy. The surface roughness increased as laser frequency increased. The surface roughness decreased and then increased with the increase of pulse energy. Through laser parameter optimization, a high quality polished surface without cracks, pits and debris redopesition was obtained under laser frequency of 40 kHz and pulse energy of 40 μJ. At this point, the average removal depth of 32.19 μm and the average surface roughness of 0.72 μm were obtained. The proposed method in this paper significantly improve surface finishment and higher dimensional accuracy of the machined SiC ceramic components.

中文翻译：

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水下飞秒激光抛光SiC陶瓷的研究

摘要 由于碳化硅陶瓷硬度高、脆性大，难以加工成具有所需表面质量和尺寸精度的结构陶瓷部件。本文提出了一种水下飞秒激光抛光SiC陶瓷的方法。详细研究了激光频率和脉冲能量对水下飞秒激光加工过程中抛光 SiC 陶瓷的表面形貌、3D 轮廓、深度和表面粗糙度的影响。实验结果表明，随着激光频率和脉冲能量的增加，水下抛光过程中的去除深度先增大后减小。表面粗糙度随着激光频率的增加而增加。随着脉冲能量的增加，表面粗糙度先减小后增大。通过激光参数优化，在 40 kHz 的激光频率和 40 μJ 的脉冲能量下，获得了没有裂纹、凹坑和碎屑再沉积的高质量抛光表面。此时，平均去除深度为 32.19 μm，平均表面粗糙度为 0.72 μm。本文提出的方法显着提高了加工后的 SiC 陶瓷部件的表面光洁度和更高的尺寸精度。