Method of manufacturing carbon-carbon composite brake disks

A method of manufacturing a part made of carbon—carbon composite material, the method comprising forming a three-dimensional fiber structure, compressing the fiber structure to obtain a fiber preform of shape close to that of the part to be manufactured, holding the preform in its compressed state, and densifying the preform, the method being characterized in that:

• the three-dimensional fiber structure is formed by superposing and needling layers of felt constituted by fibers having a mean length lying in the range 10 mm to 100 mm, said felt having a fiber volume fraction lying in the range 7% to 15%;
• the layers of felt are needled as they are superposed;
• each layer of felt is needled, and the number of needle strokes per unit area and the penetration depth of the needles in the fiber structure being formed are controlled so as to obtain needling of predetermined density in the thickness of the fiber structure;
• the number of needle strokes per unit area and the penetration depth of the needles are controlled so as to obtain constant needling density through the entire thickness of the fiber structure, thereby imparting a quasi-isotropic character thereto;
• the fiber structure is impregnated with a liquid composition, said impregnation being one of prior to being compressed and after being compressed;
• then
• the fiber structure is compressed so as to obtain a preform having a fiber volume fraction of not less than 20%;
• the preform is held in the compressed state by injecting the liquid composition containing the bonding agent inside tooling in which the preform is compressed said bonding agent capable of bonding together the fibers of the preform;
• the holding of the preform in the compressed state comprises impregnating the preform with a liquid composition containing a resin;
• and
• a resin is used having a non-zero coke content, and the resin is carbonized by heat treatment performed on the preform prior to densification thereof by chemical vapor infiltration.