High-Temperature Materials and Components for Pressure Gain Combustion

Conventional air-breathing engines are currently based on deflagration, but these engines are limited in further progress due to the already high, but limited, efficiency of this thermodynamic cycle. However, due to the thermodynamic differences between detonation and deflagration, a shift in the focus of research has gone towards detonation engines. The release of heat in detonation is much faster, entropy increase is lower, and peak temperatures are 20-40% higher than in deflagration. Based on thermodynamic analysis, the specific impulse can be up to 30% greater using an RDE compared to a traditional engine. However, the extreme environment created by the detonation causes massive erosion of the current hardware. Therefore, to advance RDE development, high-temperature materials or coatings are needed. Plasma Processes has produced coatings from high-temperature materials, such as platinum group and refractory metals, as well as oxides and carbides. For this Phase I, Plasma Processes proposes to produce eight material coating systems of three types: metal-metal, metal-metal-oxide, and CMC-metal. Coupons will be hot-fire tested in collaboration with ISSI in an RDE environment. The results of this testing will lead to the conceptual design of flight-weight combustion chamber components.