NASA and DoD are seeking high-performance, lightweight liquid rocket combustion chambers with future performance goals that cannot be achieved using state-of-the-art actively cooled metallic liners, silicided C103, or even carbon fiber-reinforced silicon carbide (C/SiC) ceramic matrix composites (CMC). Ultramet has previously developed and successfully demonstrated carbon fiber-reinforced zirconium carbide (C/ZrC) and zirconium-silicon carbide (C/Zr-Si-C) matrix CMCs for use in liquid propellant applications up to 4200o
F. In Phase I, Ultramet demonstrated the feasibility of combining the light weight of C/C with the oxidation resistance of ZrC and Zr-Si-C matrix composites in a unique system composed of a C/C primary structure with an integral CMC liner. The system effectively bridges the gap in weight and performance between coated C/C and bulk CMCs. Rapid fabrication was demonstrated through an innovative variant of Ultramet's melt infiltration refractory composite processing technology. In Phase II, Ultramet will team with ATK-GASL for process optimization, component fabrication, and comprehensive testing of lightweight, high-strength, elevated temperature oxidation-resistant liquid rocket combustion chambers. The fully developed system will have strength that is comparable to that of C/C, low density comparable to that of C/SiC, and ultrahigh temperature (>4000o
F) oxidation stability.