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Requirements for advanced rocket propulsion systems are becoming increasingly more demanding. The use of high temperature capable materials in such systems, including applications in liquid rocket engines and solid rocket motors, offers potential benefits of increased performance and/or efficiency based on the engine operating cycle. For the ultimate in high temperature capability, refractory metals, ceramics, ceramic matrix composites (CMCs), and carbon/carbon (C/C)composites each provide particularly beneficial attributes, but with selected limitations. Refractory metals are relatively tough and durable, provide impermeable structures, and can be conventionally fabricated, but are relatively dense, leading to heavyweight structures. Monolithic ceramics generally lack desired toughness and durability. CMCs offer substantially improved toughness over their monolithic counterparts and are relatively lightweight, but are permeable and difficult to join to conventional structures.

Use of continuous fiber reinforced ceramic matrix composites (FRCMC) for turbopump hot section components offers a number of benefits. The performance benefits of increased turbine inlet temperature are apparent and readily quantifiable. Perhaps less obvious are the potential benefits of increased component life. At nominal turbopump operating conditions, FRCMC offer increased operating temperature margin relative to conventional materials. This results in potential for significant life enhancement. Other attributes (e.g., thermal shock resistance and high cycle fatigue endurance) of FRCMC provide even greater potential to improve life and reduce maintenance requirements. Silicon carbide (Sic) matrix composites with carbon fibers (C/SiC) do not degrade when exposed to hydrogenrich steam for 10 hours at 1200°C. This FRCMC is resistant to thermal shock transients far in excess of those anticipated for advanced, high temperature turbomachinery.