Ultrahigh Temperature Oxidation-Resistant Ceramic Matrix Composite for Rocket Propulsion Components

"Future Air Force space, missile, and aircraft systems require advanced high temperature materials to meet projected performance requirements. Rocket engine and turbine engine programs such as the IHPRPT and IHPTET initiatives, respectively, are intendedto double next-generation propulsion capabilities. Reaching this aggressive goal demands the implementation of high temperature capability, environmentally resistant, lightweight material systems. Prominent among the alternative materials underconsideration for such applications are ceramic matrix composites (CMCs). Recent Air Force and NASA programs have considerably progressed the development of CMCs for ~2500¿F combustion environments, but additional work is required to extend current CMCcapabilities to temperatures of 3500¿F. In this project, Ultramet proposes to demonstrate the feasibility of fabricating and using an ultrahigh temperature capable CMC using a hafnium carbide/silicon carbide (HfC/SiC) matrix analogous to Ultramet'sUltra2000TM microlayered HfC/SiC coating system that has previously been shown to be effective for high temperature oxidation protection of carbon/carbon (C/C) and CMCs. Specifically, several innovative variants of chemical vapor deposition (CVD)processing will be evaluated as potential methods for densifying HfC/SiC matrix CMCs, and the resultant structures will be characterized for potential aerospace applications as a demonstration of feasibility.