Abstract: A process for making a ribbed light weight composite mirror unit. Preferred embodiments are silicon carbide composite structures. Preferred structures comprise a front smooth silicon carbide surface supported by a silicon carbide ribbed back support. The ribbed back support may be produce by milling out portions of SiC block or by the joining of multiple simple shapes to form the ribbed support. At least the smooth front SiC surface is produced using a chemical vapor composite process as described in the Background Section. These include very large mirrors that resist gravitational sagging and smaller scanning and stepping mirrors that can be pointed quickly and accurately with minimal hysteresis. Preferred milling techniques include precision water jet milling. Special bonding techniques are described to produce ribbed support from multiple parts.

Abstract: A chemical vapor composite process for producing high purity, fully dense refractory ceramics in complex geometric shapes. Preferred products are suitable for leading edge protection of very high speed space and air craft. The process is derivative of conventional chemical vapor deposition, but is able to create ceramic articles that are free of the residual stress normally associated with chemical vapor deposition. Parts and products produced have high purity, residual stress-free material of unlimited thickness in a great variety of geometries. Leading edge protective parts can be made much thicker than typical prior art ceramic parts so that the parts produced can assume load bearing function. And the parts provide much higher thermal conductivity than the prior are SiC covered carbon-carbon composite protective parts.

Abstract: A method for forming within a reactor having a work zone of at least one cubic meter, composite articles particularly ceramic composites articles, for high temperature applications. The invention provides composite articles formed from the deposition on hot surfaces of a chemical vapor having entrained solid particles. A composite material is produced comprising a chemical vapor deposition matrix with the solid particles dispersed within the matrix. Applicants have designed reactors with work zones much larger than prior art CVC reactors greatly improving production efficiency. In a preferred embodiment the work zone volume is about 3.37 cubic meters. 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.