中文摘要：

利用X射线衍射仪(XRD)和扫描电子显微镜(SEM)等检测设备,观察并研究了原位自生C/C复合材料SiC涂层的物相组成和显微结构特点,并根据SiC固态相变规律和元素互扩散原理,探讨了低压Ar气氛反应烧结制备SiC涂层的形成机理。结果表明,低压保护气氛的引入显著提高了反应烧结过程中液态Si在C/C复合材料表面的润湿性,促进C、Si原子互扩散。在此条件下,多晶Si粉与石墨碳反应形成β-SiC稳定相,且该涂层内部衬度均匀,具有鳞片状和细针状纳米晶须结构,从而改善了C/C复合材料的生物相容性。

英文摘要：

SiC coating was prepared by low pressure reaction sintering in Ar atmosphere .The phase constituents and microstructure were characterized by means of XRD and SEM .Meanwhile , the SiC coating formation mechanism was studied in accordance with the element interdiffusion principle and the solid phase transformation law .The results indicate that the low-pressure protective atmosphere significantly improves the liquid Si wettability on C/C composite and atom interdiffusion during the coating preparation .Therefore , Si powders can react with graphite to form β-SiC under the annealing temperature slightly higher than the Si melting point .There are uniform contrasts on the planar microstructure images .The coating has scaly and fine needle-like nano-whisker structure , and the biocompatibility of C/C composite is improved.