| 摘要 |
A method for forming, within a reactor having a work zone of at least one cubic meter, composite articles, particularly ceramic composite articles, for high temperature applications. The invention provides composite articles formed from the deposition as a solid matrix on hot surfaces of a chemical vapor having entrained solid particles. A composite material is produced comprising the chemical vapor deposition matrix with the solid particles dispersed within the matrix. By carefully controlling the reactor gas flows and pressure within a large work zone, as well as the number of solid particles per flow rate of reactor gas, Applicants are able to efficiently produce composites with substantially improved quality as compared with CVD produced articles and as compared with articles produced with prior art CVC processes. In preferred embodiments a special coating is placed on the substrate, so that after the composite material (such as a silicon carbide composite) is deposited and the substrate with the deposited material is cooled down, the deposited material is easily removed having a shape matching the substrate with precision so that polishing is minimized or rendered unnecessary. In preferred embodiments the substrate is silicon carbide and the coating is a layer of silicon dioxide-carbon and the deposited material is a silicon carbide composite material.
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