Abstract:Hypersonic vehicles face intense aerodynamic heating during flight, and C/C composites have received widespread attention in the aerospace field because of their excellent high-temperature thermal stability, but there is also a problem of insufficient high-temperature oxidation resistance. In this paper, composite powder materials were prepared using zirconium boride, silicon carbide, and tantalum disilicide as raw materials. A high temperature anti-oxidation ceramic coating was prepared on the surface of the C/C substrate by atmospheric plasma spraying (APS) process. SEM, EDS and other tests were employed, the phase and microstructure of the spray-dried powder and coating were characterized, and the oxyacetylene flame was used to test the coating sample at 1800℃ for 300 seconds. The research results show that the addition of TaSi2 can reduce the eutectic temperature of the composite powder and more eutectic structure has been formed during spraying. Meanwhile, the powder deposition efficiency has been improved. The ZrB2/SiC/TaSi2 ceramic composite coatings prepared by atmospheric plasma spraying shows excellent high-temperature oxidation resistance and no obvious flaking and breaking can be observed. TaSi2 can promote the formation of stable eutectic oxide and supplement the volatilized glass phase during the ablation process. The dense Zr-Ta-O eutectic oxide has been formed and plays a role as an oxygen barrier, thus leads to the better ablation resistance of the coatings.