“Thermochemical stability of high-temperature materials in extreme environments”
High temperature materials capable of surviving in extreme environments of engines or thermal protection systems for flight vehicles are in demand to improve vehicle performance. These materials require thermochemical stability to withstand high temperature reactive combustion or re-entry environments. Furthermore, the ability to understand degradation mechanisms leading to thermochemical life prediction is critical for use of new materials systems in these demanding environments. In this presentation, the fundamental degradation mechanisms of rare earth silicate coatings for use on hot section turbine engine components and the oxidation of high-entropy early transition metal carbides proposed for re-entry thermal protection systems on hypersonic vehicles will be addressed. Development of laboratory capabilities to provide relevant materials test environments and understanding of thermodynamic and kinetic factors leading to materials degradation will be explored. Challenges for testing and improved materials lifetimes in each application will be identified.