SiC-coated C / C composites

摘要

PURPOSE: To improve the thermal shock resistance, mechanical strength, high quality and useful life by forming a specific layer between a C/C composite substrate containing C fiber and an SiC layer. ;CONSTITUTION: A C/C composite substrate 5 containing carbon fiber is subjected to vapor growth vacuum depositing reaction in the presence of SiCl₄, etc., in a furnace to form a porous SiC film 3. The surface layer part of the C/C composite material 1 is then subjected to partial silicifying treatment in the presence of SiO glass, etc., at about 1500°C to form a reinforced layer 4, composed of C fiber 8 having only the silicified surface layer part and a silicified part 9 and having the thickness of (7/10) to (10/7) that of the SiC layer 2 and the diameter of 10 to 30 times that of the C fiber 10. The total cross-sectional area of the silicified part 9 is (1/9) to 1 that of the C fiber 8. The silicified material is then subjected to vacuum depositing reaction in the presence of a desired reactional gas to form an SiC film 2 composed of an SiC columnar crystal. The silicified layer in the surface layer part is integrated with a porous SiC film 3. Thereby, the objective SiC-coated C/C composite material is produced.;COPYRIGHT: (C)1993,JPO&Japio