An AlPO4/SiC coating prepared by pulse arc discharge deposition for oxidation protection of carbon/carbon composites

•Pulse arc discharge deposition was developed to prepare the AlPO4 coating.•An AlPO4 coating was deposited on the surface of SiC bonding layer.•The influence of pulse duty ratio on the as-prepared coatings was investigated.•The AlPO4/SiC coating can protect C/C composites from oxidation in air at 1773 K.

Pulse arc discharge deposition was developed to prepare an oxidation-protective AlPO4 coating for SiC pre-coated carbon/carbon composites (SiC–C/C). The influence of pulse duty ratio on composition, microstructure and oxidation resistance of the as-prepared coatings was investigated. Results show that thickness, compactness and oxidation protective property of the AlPO4 coating were improved with the increase of pulse duty ratio from 10% to 30%. The multi-layer coating prepared at a pulse duty ratio of 30% exhibits good oxidation protective property, which can effectively protect C/C composites from oxidation in air at 1773 K for 148 h with a weight loss of 0.82%.