Method of fabricating a friction part out of carbon/carbon composite material
View Patent ↗A method of fabricating a friction part out of carbon/carbon composite material, the method including obtaining a three-dimensional fiber preform of carbon fibers impregnated with a solution or a suspension enabling a dispersion of refractory metal oxide particles to be left on the fibers of the preform; applying heat treatment to form a metallic carbide by a carboreduction reaction of the refractory oxide with the carbon of the fibers; continuing the heat treatment until the carbide is transformed into carbon by eliminating of the metal; and then densifying the preform with a carbon matrix by chemical vapor infiltration.
1. A method of fabricating a friction part out of carbon/carbon composite material, the method comprising:
obtaining a three-dimensional fiber preform of carbon fibers impregnated with a solution or a suspension enabling a dispersion of refractory metal oxide particles to be left on the fibers of the preform;
applying heat treatment to form a metallic carbide by a carboreduction reaction of the refractory oxide with the carbon of the fibers;
continuing the heat treatment until the carbide is transformed into carbon by eliminating of the metal; and then
densifying the preform with a carbon matrix by chemical vapor infiltration.
2. A method according to claim 1 , wherein the heat treatment is performed under an inert atmosphere.
3. A method according to claim 1 , wherein the heat treatment is performed under an atmosphere made up of an inert gas and oxygen at a concentration lying in the range 2 ppm to 250 ppm.
4. A method according to claim 1 , wherein the heat treatment is performed at a temperature lying in the range 1450° C. to 2300° C.
5. A method according to claim 1 , wherein the heat treatment is performed for a total duration of not less than 2 h.
6. A method according to claim 1 , wherein the preform is impregnated by a colloidal suspension of oxide particles.
7. A method according to claim 1 , wherein the preform is impregnated by a sol-gel containing at least one oxide precursor.
8. A method according to claim 1 , wherein the oxide introduced into the fiber preform by impregnation represents 0.01% to 10% by weight of the weight of the fiber preform prior to impregnation.
9. A method according to claim 1 , wherein the following are performed in succession: a step of making the fiber preform; and a step of impregnating the fiber preform with the solution or the suspension.
10. A method according to claim 1 , wherein the following are performed in succession: a step of impregnating a two-dimensional fiber texture with the solution or the suspension; and a step of making the impregnated fiber preform from the impregnated fiber texture.
11. A method according to claim 1 , wherein the following are performed in succession: a step of impregnating yarns with the solution or the suspension; a step of making an impregnated two-dimensional fiber texture from the impregnated yarns; and a step of making the impregnated fiber preform from the impregnated fiber texture.
12. A method according to claim 1 , wherein a carbon precursor is added to the solution or the suspension.
13. A method according to claim 12 , wherein the carbon precursor is a polysaccharide.
14. A method according to claim 1 , wherein the refractory oxide is SiO 2 .