摘要
采用脉冲电弧放电法在SiC-C/C复合材料表面制备硼化硅和硅化钼的复相(SiB6-MoSi2)抗氧化涂层.借助X射线衍射、扫描电子显微镜对复合涂层的晶相组成、显微结构和抗氧化性能进行了表征与测试.研究了不同晶相组成(m[MoSi2]/m[SiB6]=Cp)对SiB6-MoSi2涂层显微结构的影响.结果表明:当晶相组成m[MoSi2]/m[SiB6]=1∶4时,制备的涂层致密均匀,在1 773K氧化156h后失重仅为2.12%,复合涂层氧化失效是由于长时间氧化后涂层挥发变薄,不能及时有效的愈合气相(CO和CO2)的逸出产生的氧化孔洞等缺陷导致的.
A SiB6-MoSi2anti-oxidation coating was prepared on SiC pre-coated C/C composites by pluse arc discharge deposition.The phase compositions,microstructures and anti-oxidation properties of the as-prepared multi-coatings were characterized by XRD,SEM and isothermal oxidation test.The influence of phase composition on the microstructure was investigated.Results show that the dense and homogeneous of the SiB6-MoSi2 coating was achieved when the phase composition m[MoSi2]/m[SiB6]=1∶4.The as-prepared coatings exhibit excellent anti-oxidation property,which could effectively protect C/C composites from oxidation at 1 773 Kin air for 166 hwith a weight loss of 2.12%.The anti-oxidation capability decrease of the coating is attributed to the generation of oxidation holes and microcracks which due to the volatilization of borosilicate glass layer and the escape of the gas phase（CO and CO2）.
出处
《陕西科技大学学报（自然科学版）》
2014年第5期36-41,共6页
Journal of Shaanxi University of Science & Technology
基金
国家自然科学基金项目(51172134
51272146)
陕西省科研创新团队计划项目(2013KCT-06)
