Investigating Multi-Layered Cold Spray Technology for Spacecraft Thermal Protection Systems

The extreme thermal and mechanical conditions of atmospheric reentry demand robust and reusable thermal protection systems (TPS). This project investigates the feasibility of using cold spray, a solid-state deposition method, to develop a multi-layered TPS capable of withstanding high-temperature environments while enabling faster refurbishment between missions. Traditional ablative TPS are single-use and time-sensitive to refurbish, motivating the need for an innovative approach. This study introduces a four-layer TPS architecture with distinct functional roles: a convective heat-resistant surface layer, a load-buffering intermediate later, a high-performance insulation layer, and a mechanically supportive substrate. Cold spray is evaluated for its ability to deposit metallic and metal-ceramic composites onto curved surfaces without degradation. Using 2D axisymmetric CFD simulations at Mach 2 and scaled data for expected peak heating of Mach 12, the thermal environment of a capsule side panel was modeled to inform material selection. Preliminary results suggest that cold spray is most viable for substrate and intermediate layers in low-curvature regions, though the lack of commercially available ceramic-metallic powders limits full implementation. Future success depends on the developing compatible powders and addressing thermal barrier interfaces to prevent delimitation. This foundational work supports continued exploration of cold spray TPS technologies for reusable spacecraft applications.