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The application of carbon fiber epoxy resin composite (CFRP) in the aerospace industry is limited by the laser treatment, because of the poor oxidation resistance and anti-laser ablation performance of the composites. The application of a coating on components is an effective method to improve their laser ablation resistance. The nitride coatings, consisting of Si3N4, AlN, BN, and an epoxy resin, were applied onto the CFRP using brush painting. When irradiating at 100 W/cm2 for 5 s, the damage has occurred on the coating with Si3N4 and AlN, and the BN coating remains original morphology at 100 W/cm2 for 20 s. With the power density has increased to 200 W/cm2, the serious ablation damage occurs in the BN coating irradiated for 10 s. Due to the heat absorption of resin pyrolysis and the low thermal conductivity of CFRP, the highest back-surface temperature is only 75 °C. The laser protection performance of CFRP should mainly improved by increasing the reflectivity of the coating. [ABSTRACT FROM AUTHOR]

Further utilization of polymer matrix composites (PMCs) in the aerospace industry is threatened by the development of laser weapons, resulting from weak oxidation resistance, low operation temperature and poor anti-laser ablation performance of the PMCs. Preparing an adhesive inorganic coating on the surface of components is an effective method to improve the laser irradiation resistance. Anti-laser ablation coatings composed of ZrO as pigment and sodium silicate as binder with different curing agents (including SiO and NaSiF) are fabricated on the PMCs substrate with brush painting. Influence of the different curing agents on anti-laser ablation of the coatings at the laser wavelength of 1064 nm is investigated. The rear surface temperature of substrate with coatings, containing SiO and NaSiF, decreases from 240 to 60 and 70 °C, respectively, when testing at 1000 W for 5 s. After irradiation test at 1000 W for 10 s, the coating with SiO as curing agent shows slight molten state on the surface, while the coating with NaSiF is broke down, because coating containing SiO possesses more compact microstructure and fewer cracks than that with NaSiF. [ABSTRACT FROM AUTHOR]