Effect of coating contained P, B, Si compound on the anti-oxidation properties of C/C composites

Used P, B, Si compound as the main component of anti-oxidation coating of C/C eomposites, the samples were treated at 700 ℃ and 900 ℃ respectively. The morphologies of these C/C composites samples with anti-oxidation coating were observed by SEM, the weight loss were test by electro-balance. The results show that the number of soaking and coating have obvious effect on properties of the coatings anti-oxidation. The samples with the best anti-oxidation were treated at 700 ℃ for 10 h, the weight loss is only 0.26％, and the samples were treated at 900 ℃ for 10 h, the weight loss is below 2％. The gathering and volatilization of the low temperature melting component in the coating make the coating's anti-oxidation property decreased.