Lightweight Hybrid Ablator Incorporating Aerogel-Filled Open-Cell Foam Structural Insulator, Phase II

In previous work for NASA and DoD, Ultramet developed lightweight open-cell foam insulators composed of a carbon or ceramic structural foam skeleton filled with a high temperature nanoscale aerogel insulator. Structural integrity and high insulation behavior have been demonstrated when used in combination with a non-ablating, coated carbon/carbon or ceramic matrix composite outer shell. In Phase I, Ultramet demonstrated the initial feasibility of a foam-reinforced hybrid ablator/aerogel insulator thermal protection system (TPS) in which a portion of the thickness (front face) of a low thermal conductivity structural foam was infiltrated with an ablative material and the remainder of the thickness (back face) was filled with the high temperature aerogel insulator. The potential benefit is a reduction in the ablator mass required to reject the aerothermal heat load. The three-dimensionally interconnected foam reinforcement is anticipated to provide increased char retention relative to alternative fiber and honeycomb reinforcements. The vehicle interface temperature will be controlled by the highly insulating aerogel-filled portion of the foam structure. In Phase II, Ultramet will team with Materials Research & Design (MR&D) for continued thermomechanical design optimization, and ARA Ablatives Laboratory for ablator infiltration of Ultramet structural foam. Performance will be evaluated through high heat flux ablation testing and a demonstration of scaleup potential up to 18" diameter.