Method for producing SiC/SiC composite material
A method for producing SiC/SiC composite material according to the present invention includes impregnating a substrate with a slurry containing particles of a flaky lubricant to obtain an impregnated body, drying out a solvent of the slurry from the impregnated body, forming an interface layer on surfaces of the SiC fibers by bending the impregnated body, and transferring the particles of the flaky lubricant to the surfaces of the SiC fibers while stretching the particles, and forming a SiC matrix inside the substrate on which the interface layer is formed. Since a thin interface layer of the flaky lubricant can be formed on the surfaces of the SiC fibers by transferring the flaky lubricant to the surfaces of the SiC fibers, the interface layer reaching inside of the substrate can be easily formed.
1. A method for producing SiC/SiC composite material including a substrate formed of a strand formed by bundling a plurality of SiC fibers, and a SiC matrix, the method comprising steps of:
impregnating the substrate with a slurry containing particles of a flaky lubricant formed of a material having a layered crystal structure and having a first particle size to obtain an impregnated body, wherein the substrate comprises at least one bundle of SiC fibers,
drying out the slurry to remove a solvent thereof from the impregnated body;
bending the impregnated body to modify the particles of the flaky lubricant having the first particle size, and dislodge particles of the flaky lubricant having a second particle size from the fibers, the second particle size being smaller than the first particle size;
forming an interface layer on surfaces of the SiC fibers by attaching the dislodged particles of the flaky lubricant, having the second particle size, to the surfaces of the SiC fibers; and
forming a SiC matrix inside the substrate on which the interface layer is formed using chemical vapor infiltration, polymer infiltration and pyrolysis, or melt infiltration.
2. The method for producing SiC/SiC composite material according to claim 1 , wherein the flaky lubricant includes at least one selected from the group consisting of carbon particles and boron nitride particles.
3. The method for producing SiC/SiC composite material according to claim 1 , wherein the slurry further contains a binder resin.
4. The method for producing SiC/SiC composite material according to claim 1 , further comprising a step of washing the strand before the impregnation step.