Abstract: The carbon-carbon composite material is obtained by densification with a pyrolytic carbon matrix originating from a precursor in gaseous state at least in a main external phase of the matrix, and, at the end of the densification, final heat treatment is performed at a temperature lying in the range 1400° C. to 1800° C.

Abstract: A method of fabricating a composite material part having carbon fiber reinforcement densified by a matrix, including making a coherent fiber preform of carbon fibers presenting holes formed from at least a first face of the preform, and densifying the preform by depositing therein a material constituting a matrix by means of a chemical vapor infiltration type process. The holes are formed by causing a plurality of non-rotary elongate tools to penetrate simultaneously, the tools being substantially mutually parallel and presenting on their surfaces roughnesses or portions in relief suitable for breaking and/or transferring fibers they encounter, the tools being caused to penetrate simultaneously by moving a support carrying the tools, and the tools being selected to have a cross-section that makes it possible to obtain in the carbon fiber preform holes that present a cross-section with a mean dimension lying in the range 50 ?m to 500 ?m.

Abstract: The carbon-carbon composite material is obtained by densification with a pyrolytic carbon matrix originating from a precursor in gaseous state at least in a main external phase of the matrix, and, at the end of the densification, final heat treatment is performed at a temperature lying in the range 1400° C. to 1800° C.

Abstract: A coherent fiber preform made of carbon fibers presents holes formed from at least a first face of the preform, and the preform is densified by depositing therein a material constituting a matrix by means of a chemical vapor infiltration type process. The holes are formed by causing a plurality of non-rotary elongate tools to penetrate simultaneously, the tools being substantially mutually parallel and presenting on their surfaces roughnesses or portions in relief suitable for breaking and/or transferring fibers they encounter, the tools being caused to penetrate simultaneously by moving a support carrying the tools, and the tools being selected to have a cross-section that makes it possible to obtain in the carbon fiber preform holes that present a cross-section with a mean dimension lying in the range 50 ?m to 500 ?m.

Abstract: A fiber preform for manufacturing a brake disk out of composite material is itself manufactured by superposing and bonding together fiber layers. Structural fiber layers (10) are used to form at least a first preform portion that is to constitute the fiber reinforcement of the brake disk core, while the or each preform portion that is to constitute the fiber reinforcement of a friction portion of the brake disk is constituted by a felt (16, 18), at least in its portion adjacent to the friction face.

Abstract: A three-dimensional fiber structure is formed by superposing layers of felt and by bonding them together by needling, then the structure is compressed to obtain a preform having a fiber volume fraction of not less than 20%. The preform is held in its compressed state by being impregnated with a liquid composition containing a bonding agent capable of bonding the fibers of the preform together. Thereafter, the preform consolidated in this way is densified, e.g. by chemical vapor infiltration.