Study on the laser ablation behavior of nitride coatings on carbon fiber epoxy resin composite

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 Si 3 N 4 , AlN, BN, and an epoxy resin, were applied onto the CFRP using brush painting. When irradiating at 100 W/cm 2 for 5 s, the damage has occurred on the coating with Si 3 N 4 and AlN, and the BN coating remains original morphology at 100 W/cm 2 for 20 s. With the power density has increased to 200 W/cm 2 , 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.