Elaboration en Continu d’un Depot Mince de Carbure Refractaire en Surface des Fibres de Carbone: Caracterisation de la Fibre C/SiC

Reactive chemical vapour deposition (RCVD) has been used for the coating of the single filaments of a PAN-based carbon yarn by SiC. A continuous process has been developped, it consists to react a mixture SiCl4-H2 with the fiber, at T 1000°C, under, atmospheric pressure. By the aid of thermodynamic calculations and experimentation, the conditions of RCVD (gaz composition, temperature, reaction time) are optimized to elabore a coating without degrading the fiber. It is shown that a SiC-β coating, 0.05 micron thick, modified slighty the characteristics and is sufficient to reduce the rate of combustion of the fibers by a factor closed to 100.