A method for improving de oxidation resistance of fiber-reinforced composite material with a glass -, ceramic - or glass ceramic matrix

摘要

According to the invention is a reinforcing fiber of the ceramic type not - oxide or of carbon for the manufacture of a composite material with a glass, glass-ceramic or ceramic matrix by a process which comprises the steps consisting in: if necessary, to oxidize the fiber at the surface or to deposit a layer of the same composition but containing oxygen, to introduce the fiber in an enclosure of chemical vapor deposition, to carry out a preprocessing at a temperature of 850 to 1250 degréc, in the presence of hydrogen, under a pressure of 50 to 300 mbar, to inject a mixture of neutral carrier gas and of ammonia, stop the injection and adjust the pressure to a value of 1 to 10 mbar, inject alcl3 in a neutral diluting gas; be carried out on the fiber a deposit of the aln by simultaneous injection of a mixture of alcl3 and of neutral carrier gas, and of a mixture of nh3 and of neutral carrier gas, so as to obtain the desired thickness of the aln; after stopping the injection, the mixture is cooled under a stream of inert gas; and to recover the fiber. & br / application to the manufacture of composite materials having a good resistance to oxidation.