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%.