3D-networked porous carbon with endothermic agents: Phase-change shield system as an advanced aerospace thermal protection system

Abstract An ablative thermal protection system (ablator) can protect re-entry vehicles from severe aerodynamic heating during re-entry. Ablators are carbon-based materials with an impregnated resin, and the decomposition of the resin during re-entry prevents a temperature increase in the components. The phenolic-impregnated carbon ablator is a well-known ablator. However, its low strength makes the design of re-entry vehicles difficult. Recently, a high-strength three-dimensional networked porous carbon called a carbon monolith (CM) was developed. No significant difference was found in the recession behavior of CMs with or without resin. In this study, a B ₄ C particle–dispersed CM (BCM) was prepared as an advanced ablator without resin. The results obtained by heat exposure simulating atmospheric re-entry conditions (arc jet test at 1.9 and 6.1 MW m ⁻² ) show that the melting of B ₄ C contributes to a decrease in surface and internal temperatures compared with CM. Because the phase change (melting of B ₄ C) acts as an endothermic agent, BCM is recognized as a type of advanced ablator termed a phase-change shield system.