Owing to their low density and exceptional ability to maintain strength at extremely high temperatures, advanced carbon-carbons (C-C) composite is the preferred structural material for atmospheric entry applications where the vehicles at hypersonic speed are exposed to extreme temperatures (2000°F to 4000°F) and oxidizing atmospheres. In addition to structural integrity at temperatures up to 4000°F, the material used for the leading edge also needs good thermal conductivity in order to spread the highly localized heat flux to a larger radiating surface and avoid thermal runaway. Operations using the advanced C-C composites are generally expensive due to high material fabrication costs and oxidation wear-out / single use. Reusable load-carrying ceramic matrix composites (CMC) have being developed for hot structure applications with some success; however, only C-C composites have shown ability to meet the extreme temperature & heat conduction requirements for leading edge applications. Building on knowledge gained with aircraft break products, a novel C-C composite architecture with readily tunable thermal mechanical properties that employs lower-cost carbon fibers and has a shorter manufacturing lead time is proposed. Additionally, nano-inhibition is proposed to mitigate the oxidation concerns, hence improved damage tolerance and structure re-usability are expected. In Phase I, Allcomp proposes to focus on the leading edge application requirements and demonstrate (1) manufacturability of a lower cost, shorter lead time C-C architecture, (2) feasibility to modulate thermal mechanical properties with preform stack design and densification process enhancements, and (3) inclusion of selected anti-oxidation technology to improve damage tolerance. Once proven, this architecture will offer other hot structure applications, such as aero-shell and propulsion components, lower cost options with improved reliability. Potential NASA Applications (Limit 1500 characters, approximately 150 words) Hot structures for both vehicle body and propulsion systems: Atmospheric entry / re-entry vehicles (aero-shell and leading edge), replacing parasitic thermal protection systems Expendable and re-usable hypersonic vehicles, (aero-shell and leading edge) Scramjet components, hot gas path Exit cones / nozzle extensions Potential Non-NASA Applications (Limit 1500 characters, approximately 150 words) Both DoD and Commercial Space / Transportation applications: Leading edges and fins for hypersonic vehicles, Re-usable load-carrying aero-shell and control surface elements, hot gas ducts for scramjet, hot gas valves, throats, nozzle extensions
