Study of Cf/SiC Composites in Linear Scanning Ablation by Femtosecond Laser

Abstract

C_f/SiC is a preferred material for high-temperature-resistant components in aerospace, but it is characterized by anisotropy, non-homogeneity, and brittleness. Femtosecond laser processing technology, characterized by high precision and small heat-affected zone, has great potential in processing C_f/SiC. In response to the problem of unclear linear scanning ablation mechanism between laser and materials, this paper conducted femtosecond laser linear ablation and simulation experiments on C_f/SiC composites, obtaining the development laws of electron as well as crystalline host lattice both in temperatures and physical morphology over time and space. The ablation mechanisms involving sublimation and ionization under femtosecond laser irradiation were revealed. It was found that laser power has a greater influence on ablation width, in comparison to scribing speed. Conversely, when compared to laser power, scribing speed has a more significant impact on ablation depth and micromorphology. Periodic structures emerged on the surface of the ablation groove in which laser power was below 2 W and the scribing speed was above 100 mm/s. The ablation parameters were optimized, providing theoretical support and data basis for high-efficiency, high-quality femtosecond laser processing of C_f/SiC composites.