Effect of energy density and feeding speed on micro-holes drilling in SiC/SiC composites by picosecond laser

Picosecond laser machining is an important modern technology for materials with high hardness. In this paper, micro-holes with several hundred micrometer diameter were drilled in SiC/SiC composite using picosecond laser, and the quality of the micro-holes under different machining parameters was investigated in detail. The results indicated that energy density and feeding speed had remarkable effect on the micro-hole quality. The roundness of the micro-holes on the laser entry side was rarely affected by energy density and feeding speed. However, the roundness of the micro-holes on the laser exit side and micro-hole diameters along processing direction were quite sensitive to the energy density and feeding speed. Feeding speed had little influence on the quality of drilling holes, except for more debris on the entry side with 11.2 μm/s feeding speed.