Novel High Temperature, High Strength, Oxide-resistant Composites for Wind Tunnel

To produce a hypersonic flight vehicle, it is necessary to utilize an airbreating propulsion cycle. Most US aeropropulsion programs focus on the operation of a multi-mode engine with a ramjet and scramjet cycle that allows speeds from Mach 2 to over Mach 8. The testing of these engines is possible on the ground, in specially designed wind tunnels. The desire to simulate flight at Mach 8 or more requires the facility nozzle to be operated at pressures up to 1800 psi and temperatures around 4500 K. The development of such nozzles with moderately complex shapes and throat diameters ranging from 0.5 inch to 2.5 inches challenges the material processing community. There is the need for the development of a new class of material that will have high strength, high temperature and oxidation resistance. This proposal provides the solution to this problem through the development of a cost effective novel hybrid composite concept where the inner contour of the nozzle is made of a high temperature oxidation resistant composite which then transitions to an outer skin made of a fiber reinforced high temperature, high strength, oxidation resistant material. The success in Phase I will have far reaching implications for DoD.