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C/SiC composite has been widely used as a high‐temperature material for engineering components due to its excellent thermal properties. Facing the rapid development and threat of high‐energy laser, study on the ablation resistance under laser irradiation is strongly required. In this work, a continuous high‐energy laser was applied to explore the laser ablation behavior and mechanism of C/SiC composite. From the results, C/SiC composite shows different morphologies when irradiated at various laser power densities for 500 and 700 W/cm2. We divided the ablation area into three regions; the central, transition, and edge regions, where the formation of SiO2, SiO, and the breakage of carbon fiber were observed. The generated highly reflective SiO2 layer reduces the absorption of laser energy, which is beneficial to lower the back‐surface temperature and reduce the damage of composite. In addition, we put forward the ablation physical models and ablation mechanisms irradiated at different power densities. The work provides a basis for the laser ablation resistance of C/SiC composites under different conditions. [ABSTRACT FROM AUTHOR]

Laser attracts more attention and it could cause material failure by its high energy. Carbon fiber resin composites are widely used in aerospace vehicles experiencing dramatic damage to their surface if exposed to high-energy laser irradiation. The available studies on irradiation behavior are mainly focused on pulsed lasers and bulk composites, and investigations of thin laminar structures under continuous-wave laser irradiation have rarely been reported. In this study, the damage behavior of laminar carbon fiber epoxy resin composites (CFE composites) was studied. Using a threshold model of resin pyrolysis, CFE composite is observed to be damaged at 0.18 s when irradiated at 100 W/cm2, and if the laser power density is increased to 200 W/cm2 for 2 s, no resin remains on the fiber surface, which is now completely exposed. With an increase in power density and irradiation time, the ablation rate always shows an upward trend: the ablation region expands and the separation of layers in the interior appears, which can reach 0.01156 g/s when irradiated at 100 W/cm2 for 5 s. The damage mechanism of CFE composite was also revealed by the temperature evolution data, thermogravimetric analysis, and composition change. [ABSTRACT FROM AUTHOR]