石墨上化学气相沉积SiC组织特征与性能

Microstructure and Performance of Chemical Vapor Deposition SiC on Graphite

利用压汞法、SEM和EDS等分析手段对石墨及化学气相沉积SiC组织结构进行了研究。石墨试样的比表面测试显示:经2200℃高温处理石墨试样的比表面积较未处理试样增大了近34%。石墨试样的孔径分布显示:高温处理石墨试样的孔径分布在<10nm和>200nm有所增加,而界于两者之间的中型孔径分布略有降低,从而证明了热处理中大量原子发生一定范围的重排。SEM和EDS分析表明,高温处理过的石墨沉积SiC具有CVI结构特征;经过高温处理的石墨SiC沉积呈CVI特征,而未经高温处理石墨沉积的SiC呈典型CVD特征。对CVDSiC/graphite再经1600℃处理,对强度影响不大。

The microstructure of graphite and CVD （Chemical Vapor Deposition） SiC/Graphite has been studied by mercury injection method, SEM and EDS. Measurement of the specific surface area of graphite showed that the specific surface area of the heat treatment graphite at 2200℃ was more 34% than that of untreatment graphite. The pore size distribution of graphite showed that of the pore size of 〈 10 nm in the heat treatment graphite and 〉200 nm increase, but the medium pore size distribution between 10 nm and 200 nm reduce, while SiC/Graphite sample without heat treatment presented CVD properties obvious. The experiment results indicated that CVD SiC/Graphite sample treated at high temperature possessed CVI structure properties by means of SEM and EDS, which showed that atomic arrangement occurred during heat treatment process. The strength of CVD SiC/Graphite was not effected by heat treatment at 1600℃.