SiC涂层对C/C复合材料高温氧乙炔焰烧蚀性能影响  

Effect of SiC coating on ablation resistance of C/C composites under oxyacetylene torch flame

作　　者：苏哲安[1] 杨鑫[1] 黄启忠[1] 黄伯云[1] 李建立[1] 张明瑜[1] 谢志勇[1] 

机构地区：[1]中南大学粉末冶金国家重点实验室,长沙410083

出　　处：《中国有色金属学报》2011年第11期2838-2845,共8页The Chinese Journal of Nonferrous Metals

基　　金：国家重点基础研究发展计划资助项目(2011CB605801);国家自然科学基金资助项目(50802115)

摘　　要：采用化学气相反应法在C/C复合材料表面制备抗氧化SiC涂层,借助X射线衍射仪、扫描电镜及能谱等分析手段,研究涂层的结构;通过氧乙炔焰烧蚀试验考察SiC涂层对C/C复合材料高温耐烧蚀性能影响。结果表明:SiC涂层可明显提高C/C复合材料的高温短时耐烧蚀性能,经过20 s的高温氧乙炔焰烧蚀后,C/C复合材料试样的线烧蚀率和质量烧蚀率分别为13μm/s和6.6 mg/s,SiC涂层试样的线烧蚀率和质量烧蚀率分别为22μm/s和0.5 mg/s;在烧蚀中心区,涂层试样的烧蚀以升华分解为主,同时还伴有氧化烧蚀和微区机械剥蚀;在烧蚀过渡区,涂层的烧蚀机制以热氧化和燃气冲刷为主;而在烧蚀边缘区,涂层的烧蚀则主要表现为弱氧化烧蚀。The anti-oxidation SiC coatings were prepared on C/C composites by the chemical vapor reaction（CVR） method.The structure of the coatings was studied by XRD,SEM and EDS analysis,and the effect of SiC coatings on ablation resistance of C/C composites was investigated by oxyacetylene torch flame test.The results show that the prepared SiC coatings can effectively improve the ablation resistance of C/C composites in short time ablation.After 20s ablation by oxyacetylene flame,the linear ablation rate and mass ablation rate of C/C composites are 13 μm/s and 6.6 mg/s,respectively while those of SiC coated C/C composites are 22 μm/s and 0.5 mg/s,respectively.In the ablation center,the ablation mechanism of the coated sample is sublimation and decomposition,combined with thermo-oxidation and mechanical denudation.In the transitional field,the ablation mechanism of the coating is controlled by thermo-oxidation and scouring.And in the ablation rim,the coating exhibits slight oxidation behavior.

关 键 词：C/C复合材料 抗氧化涂层 SIC 氧乙炔焰烧蚀 

分 类 号：TB332[一般工业技术—材料科学与工程]