Economical Manufacture of Refractory Ceramic Composite Aerostructure for Kinetic Energy Interceptor, Phase II

Advanced missile defense interceptors require lightweight thermal protection systems (TPS) and aerostructures designed to minimize internal temperature rise and ensure missile airframe structural integrity during flight, including operation in adverse weather. These material systems must meet various requirements such as weight, erosion/ablation performance, component survivability, and cost. Integration of the airframe and TPS components into a single unit has the potential to minimize weight, complexity, and cost. Ultramet has developed a melt infiltration process for rapid fabrication of refractory ceramic matrix composites (CMC) including matrices of zirconium carbide (ZrC), hafnium carbide (HfC), silicon carbide (SiC), and ceramic alloys comprising two or more of these. Substantial ultrahigh temperature hot gas testing of these composites has been performed with extremely good results, including testing under the MDA/SMDC/AMRDEC Composites and Advanced Materials (CAM) program. Ultramet has also developed and tested high temperature, low-cost insulators composed of open-cell carbon foam that is filled with a low thermal conductivity carbon aerogel insulator. The potential exists to combine and optimize melt infiltrated CMCs with foam-based insulators that meet the demanding requirements of hypersonic airframes while demonstrating affordable processing. The Phase I project combined detailed thermal and structural analysis of advanced composite structures by Materials Research and Design, low-cost and scalable air-dried aerogel insulation materials produced by Ocellus, and ultrahigh temperature structural CMC and foam insulator materials produced by Ultramet to demonstrate the initial feasibility of a fully integrated, non-eroding, load-carrying aerostructure/TPS that can operate under high heat flux and shear conditions. In Phase II, Ultramet will team with Raytheon for optimization of materials and structures, supporting Raytheon development of an integrated nosetip/insulator for the hypersonic Kinetic Energy Interceptor (KEI) vehicle. Team members will include Materials Research and Design, which will perform comprehensive thermostructural analysis based on requirements defined by Raytheon, and Ocellus, which will continue aerogel insulation optimization in combination with Ultramet structural foam insulators and high temperature CMC aerostructure development. Performance testing will include hydrometeor erosion testing at NASA Marshall and high temperature oxidation testing at the Air Force LHMEL facility.