HU Chuanqi, HUANG Xiaoting, LIU Hailin, HUO Yanli, YANG Taisheng, TANG Jie, CHEN.Yufeng
(China Building Materials Academy Co., Ltd., Beijing 100024)
Abstract：A silicon carbide (SiC) coating was deposited on the surface of graphite substrate by chemical vapor deposition (CVD) using methyltrichlorosilane (CH3SiCl3, MTS) and high-purity hydrogen (H2) as raw materials. The microstructure of the SiC coating was observed by scanning electron microscopy (SEM) and the elements composition of it was analyzed by energy spectrum analysis (EDS). The surface microstructure was observed by the metallographic microscope, the surface roughness data was obtained by the surface roughness profiler, and the density of the SiC coating was tested by the drainage method. The results show that, when using as a substrate material a high density, high strength and high uniformity graphite, for example, the granite with the density of 1.88 g/cm3 and three-point flexural strength of 79.30 MPa, a high quality SiC coating could be prepared under an optimized process conditions, its density, porosity and surface roughness being 3.193 g/cm3, 0.50 % and 1.0157 μm, respectively.
Key words: graphite substrate; chemical vapor deposition; SiC coating; quality of coating; analysis