CARBON-FIBER REINFORCED CARBON COMPOSITE MATERIAL HAVING OXIDATION RESISTANCE AND PRODUCTION THEREOF

摘要

PURPOSE:To obtain a composite material repeatedly usable in an oxygen- containing atmosphere at high temperatures by previously producing silicon carbide on the outer surface of a specific carbon-fiber reinforced carbon composite material, then forming a silicon carbide film and impregnating the resultant film with boron oxide. CONSTITUTION:Metallic silicon powder is applied to the outer surface of a carbon-fiber reinforced carbon composite material in which cloths woven of carbon fiber are laminated at 0 deg./90 deg. and the resultant composite material is heat-treated in an inert atmosphere to previously produce silicon carbide on the outer surface thereof. A film composed of silicon carbide is then formed on the aforementioned outer surface by a vapor chemical reaction deposition method. The film is subsequently impregnated with boron oxide or a mixture of the boron oxide with silicon oxide to afford the objective composite material. In the above-mentioned method, for example, methods for reducing silicon tetrachloride with hydrogen and reacting a hydrocarbon such as methane therewith or thermally decomposing methyltrichlorosilane are used for forming the silicon carbide film.