C/C复合材料Ta2O5-TaC/SiC抗氧化抗烧蚀涂层研究

采用包埋法和低压化学气相沉积(CVD)法在碳/碳(C/C)复合材料表面依次制备了Ta2O5-TaC内涂层和SiC外涂层,用X射线衍射分析(XRD)、扫描电镜(SEM)及电子能谱(EDS)对涂层的相组成、微观形貌和元素组成进行了分析,研究了涂覆涂层后C/C复合材料在1 500℃静态空气中的防氧化性能及在氧-乙炔烧蚀中的抗烧蚀性能。结果表明:采用两步法制得的Ta2O5-TaC/SiC复合涂层结构致密,该复合涂层有效提高了C/C复合材料的抗氧化和抗烧蚀性能;Ta2O5-TaC/SiC复合涂层在1 500℃静态空气环境下可对C/C复合材料有效保护100 h以上;涂层试样在氧乙炔烧蚀环境中烧蚀60 s表明涂层可将C/C复合材料的线烧蚀率降低47.07%,质量烧蚀率降低29.20%。

Ta2O5 -TaC/SiC Multilayer Coating for Protecting C/C Composites against Oxidation and Ablation

To improve the property of anti-oxidation and anti-ablation of carbon/carbon （C/C） composites at high tem-perature, Ta2O5-TaC inner layer and SiC outer layer were prepared on the surface of C/C composites by pack cementation and chemical vapor deposition, respectively. Micro-structure of as-prepared coating was analyzed by XRD and SEM. The coated specimens were tested in static air atmosphere at 1 500 ℃ and oxyacetylene ablation to research their properties of anti-oxidation and anti-ablation. The results show that T2O5-TaC/SiC multilayer coating could prevent C/C matrix from oxidation in static air atmosphere at 1 500 ℃ over 100h. The linear and mass ablative rates of coated specimens could be reduced by 47.07% and 29.20% respectively after an oxyacetylene ablation test for 60 s, indicating that Ta2O5-TaC/SiC multilayer coating could effectively improve the anti-ablation property of C/C composites.