Cost effective, rapid densification of lightweight ceramic matrix composite LRE components by gas phase reaction synthesis

Sabulon, Inc. has developed novel and rapid gas phase nitridation methods which have considerable potential for manufacturing rocket nozzle components from structurally robust and thermally stable silicon-based CMC materials in more cost-effective and rapid fashion than currently available chemical capor infiltration or polymer impregnation and pyrollysis processing techniques. This proposal advocates the concept of employing reaction synthesis methods for fabricating small thrusters such as those already flown in kinetic energy weapon programs. During Phase I, a team led by Sabulon will develop and refine rapid, net-shape processing methods which are capable of producing carbon and/or ceramic fiber reinforced ceramic matrices consisting of varying phase mixtures of silicon nitride and silicon carbide. Materials made during Phase I will be screened with mechanical test and microstructural evaluation methods. In addition, constituent and bulk response of the materials will be modeled by Materials Sciences Corporation using their CLASS II finite element code. The best performing materials will be fabricated into representative CMC rocket nozzle shapes, to be tested at Rocketdyne or the Phillips Laboratory.The Phase II Program would encompass an expanded testing and design effort on the part of Sabulon, Rocketdyne, MSC, and other interested agencies, resulting in fabrication and hot-fire testing of subscale and actual CMC nozzle components.