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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]

Although the inorganic filler modified carbon-phenolic composites are widely used as thermal-structural materials in moderate ablation conditions, it is still unknown whether these composites can be used in extreme environments, such as in high-intensity continuous lasers. To investigate the effect of silicide on ablation behaviors of carbon-phenolic composites, TaSi 2 /ZrSi 2 modified carbon-phenolic composites were fabricated by compression molding and tested in a high-intensity continuous laser. Results showed that TaSi 2 /ZrSi 2 modified carbon-phenolic composites possessed a good ability to resist long-term laser ablation. As the laser ablation time increased, the ablation rate was reduced. When the ablation time was increased to 100 s, the liner ablation rate was only 0.012 mm/s. The formed double ceramic layers with TaZr 2.75 O 8 , Ta 2 O 5 , and SiC as the main phases effectively enhanced the reflectivity of the composites and obstructed laser from entering the interior. The evaporation of the pyrolysis gas and the occurrence of the carbothermal reduction reactions effectively dissipated the deposited energy. The energy dissipation mechanism based on the multi-effect synergy provided the foundation for the modified composites to possess long-term laser resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ablation mechanism of metamaterials under high-energy continuous-wave laser irradiation was for the first time revealed. • The microwave absorption performance of metamaterials under extreme laser damage conditions was firstly deeply investigated. Metamaterials, typically consisting of sub-wavelength metal-atom arrays and a dielectric layer matrix such as glass fiber reinforced epoxy resin (FR-4), have been widely used in the field of stealth equipment due to their good electromagnetic parameter designability and strong absorption for electromagnetic waves at specific frequencies. In offensive and defensive confrontations, laser weapons pose a serious threat to the survival of stealth equipment. However, the interaction mechanism between the metamaterials and laser and the effect of laser ablation on microwave absorption performance are still unclear. In this work, we firstly irradiated the double arc-shaped Cu-atom array/FR-4 matrix metamaterials by using a high-energy continuous-wave laser and studied the interaction and response mechanism between them. The high temperature caused by laser irradiation leads to the melting of the metal atoms and the pyrolysis of the resin matrix. By simulating and testing the reflection loss of the metamaterials before and after irradiation, we found that the resin pyrolysis products strongly affect the impedance matching characteristics and reduce the microwave absorption properties significantly in extreme cases. Our findings help deeply understand the interaction between the metamaterials and the laser and will show guidance in the applications involving laser-metamaterial interactions. [ABSTRACT FROM AUTHOR]