How to Make Ceramic Matrix Composites That Are Resistant to Moisture and the Environment

摘要

PROBLEM TO BE SOLVED: To provide a method for producing a ceramic matrix composite material (CMC) capable of exhibiting improved resistance to moisture and environment without loss of material performance. SOLUTION: A method for producing a ceramic matrix composite material exhibiting resistance to moisture and the environment has been developed. The method comprises depositing a diffusion barrier layer containing boron nitride on silicon carbide fibers and a moisture resistant layer containing silicon-doped boron nitride on the diffusion barrier layer, the thickness of the moisture resistant layer being diffuse. It is about 3 to about 300 times the thickness of the barrier layer. In this way, a compliant multilayer including a moisture resistant layer and a diffusion barrier layer is formed. A wet layer containing silicon carbide, boron carbide and / or pyrolytic carbon is deposited on the compliant multilayer layer. After depositing the wet layer, the slurry is infiltrated into the fiber preform containing the silicon carbide fibers. After permeating the slurry, the fiber preform is impregnated with a silicon-containing melt and then cooled to form a ceramic matrix composite. [Selection diagram] Fig. 3