Patent ID: 9611180
Date: 2017-04-04
CPC Classifications: C04B

Claim:
1. A method of fabricating a composite material part having a matrix, the majority of said matrix being made of ceramic, the method comprising: making a fiber preform from silicon carbide fibers containing less than 1 at % oxygen; depositing a boron nitride interphase on the fibers of the preform, deposition being performed by chemical vapor infiltration at a deposition rate of less than 0.3 μm/h so as to obtain coated fibers; performing heat treatment of the thus obtained coated fibers, only after the end of the deposition of the boron nitride interphase, without prior exposure of the interphase to an oxidizing atmosphere and before depositing matrix layer on the interphase, the heat treatment allowing to stabilize the boron nitride of the interphase, the heat treatment being performed on the coated fibers which comprise the fibers and the boron nitride interphase and which are deprived of any matrix layer deposited on the boron nitride interphase, the heat treatment being performed at a temperature higher than 1300° C. and not less than a maximum temperature to be encountered subsequently until a densification of the preform with the matrix has been completed; and thereafter, densifying the preform with the matrix.