Laser ablation effect of composite coating applied to aerospace material

This paper concentrates on the measurement and analysis of laser ablation effect of particularly prepared aerospace material, polycarbosilane (PCS). Laser ablation experiment setup is designed and built, based on a continuous-wave high-power solid-state laser (CWHPSSL). Metal-shell samples with composite PCS are prepared. Then a group of laser ablation experiments are performed on those samples. They are processed by laser beam with thousands of W/cm2. The results, including the ablation morphology and temperature data, are shown and discussed. Temperature data give a good demonstration of the protection effect of composite coating, and in the meanwhile the minor-morphologies in the ablated region hint the principle of PCS laser-proof effect. After that, a theoretical investigation is carried out. Fourier equation of heat conduction is applied to modeling the temperature field during ablation process. The simulation provides a good explanation on the principle of laser-proof effect of PCS composite coating. The results demonstrate that, with the protection of PCS composite coating, kilowatt-level laser only results in hundreds of Celcius temperature increment of steel substrate.