Abstract: Rotating chemical vapor infiltration (RCVI) is an improved process for fabricating C/SiC composites, and it is based on chemical vapor infiltration principle.
In RCVI process, layer-by-layer of carbon cloth and deposition of matrix were done synchronously by rotating of a graphite axis, with the result that the bottle-neck
effect of gas diffusion in traditional processes was eliminated. The effect of flux and concentration of methyltrichlorosilane (MTS, CH₃SiCl₃), deposition temperature and rotational
linear velocity of carbon cloth on deposition rate of silicon-carbide matrix, and the effect of deposition temperature on structure of silicon-carbide matrix, were studied
with lots of experiments. Three different kinds of pores, which are micro-gap around filaments, macro-holes due to weaving and spaces between plies of carbon
cloth, were rapidly filled with SiC matrix at the same time. The optimal conditions for deposition are a low pressure of 5kPa, a high temperature of 1100℃,
400 mL·min^-1 and 200 m·min^-1 flow rates of H₂ and Ar, respectively, a MTS temperature of 40℃ and a 1.1～3.5mm·min^-1
rotational linear velocity of carbon cloth.

Key words: rotating-CVI, C/SiC composites, deposition rate, matrix structure