Ceramic matrix composite

Claim 1

A process for producing a solid composite comprised of a ceramic matrix and at least a layer of a plurality of continuous Si-C-containing fibers which comprises forming a slurry of a matrix-forming material comprised of a particulate mixture of silicon nitride and a member selected from the group consisting of cordierite, a cordierite-forming composition, and combinations thereof wherein said member ranges from 1% to 50% by weight of said particulate mixture, providing at least a layer of a plurality of continuous fibers comprised of a Si-C containing material containing at least 50% by weight of silicon and at least 25% by weight of carbon based on the weight of said Si-C containing material, producing a wet preform comprised of said fibers coated with the wet solids of said slurry wherein the coated fibers in each layer are substantially parallel to each other and wherein the coatings prevent significant direct contact between the fibers, drying said wet preform to produce a dry preform comprised of said matrix-forming material and said fibers, and hot compressing the resulting preform or a sample thereof under a sufficient pressure at a temperature sufficient to generate sufficient liquid phase to sinter said silicon nitride and produce a sintered product, said compression temperature ranging from 1200° C. to 1750° C., and cooling said sintered product producing said solid composite, said composite having a porosity of less than 5% by volume, said composite containing no significant amount of reaction product of said fibers and said matrix, said matrix having a thermal expansion coefficient which is lower than that of said fibers, at least 10% by volume of said composite being comprised of said fibers.