Chemical Vapor Composite Materials for Thermal Protection Systems in Aggressive Reentry Space Vehicles

The continued study of the application of the Chemical Vapor Composites (CVC) process to thermal protection system (TPS) fabrication is proposed. The Phase I study demonstrated successful net-shape CVC Silicon Carbide (SiC) deposition of scaled nose and wing leading edge TPS structures. Phase I thermal modeling utilizing AFRL Reentry Structures Experiment (RESE) heating rates suggests peak front surface temperature will briefly exceed sublimation point of SiC. Thus, for Phase II, we propose: (Task 1) Fabrication of reinforced CVC SiC components for aero-thermal evaluation); (Task 2) High energy laser testing of CVC SiC and development of a thermal response model, to include oxidation and ablation characteristics. These studies will determine the applicability of CVC SiC to single use vehicles such as the Common Aero Vehicle (CAV) and enhanced version (ECAV). In anticipation of TPS for reusable vehicles within the FALCON/CAV program, we propose for Phase II (Task 3): Development of CVC processes for the UHTC’s zirconium carbide (ZrC) and hafnium carbide (HfC); and (Task 4) high energy laser testing and thermal response model development for ZrC based TPS. The net shape capability of the CVC process is particularly relevant to current concerns about the manufacturability of UHTCs.