Ablation of definite-depth blind holes in 2.5-dimensional C/SiC composites by nanosecond laser

Owing to the excellent physical properties of C/SiC composites, they are extensively used in extreme conditions such as nozzle jet vanes and turbine engine components. However, removing C/SiC composites using traditional machining methods is difficult. To explore the processing possibility of blind holes using a nanosecond laser, in this study, a nanosecond laser was used to ablate 2.5-dimensional C/SiC composites. First, orthogonal experiments and temperature simulations of ablating blind holes were conducted to reveal the laser processing mechanism of the 2.5-dimensional C/SiC composite blind holes, and the ablation parameters were optimized by considering their efficiency and quality. Second, the relationship between the depth of the blind holes and the number of scans was established by conducting single-factor experiments based on the optimized parameters. Finally, circular, square, and trench blind holes with depths of 1.5 mm and 2 mm were ablated successfully based on the above determined relationship, and it was verified that the depth of the blind holes in the 2.5-dimensional C/SiC composites could be ablated in a controlled manner by the nanosecond laser. This research provides references and concepts for processing definite-depth blind holes and other functionalized structures in C/SiC composites using a nanosecond laser with high accuracy and efficiency.