Microstructural Analysis of Novel Low-Density Flexible Ablators Based on Polysiloxane Resin

This research focuses on the development and characterization of novel low-density flexible thermal protection systems (TPS) materials for atmospheric reentry applications. TPS materials protect spacecraft from extreme aerodynamic heating through ablation mechanisms, where pyrolysis gases dissipate heat and a char layer provides insulation. Conventional characterization of ablative materials relies on costly experimental testing, limiting the rapid development of new material systems. This study investigates an alternative approach using microstructural analysis and computational modeling to predict key properties, such as thermal conductivity, density, and porosity. The Koo Research Group (KRG) evaluated Ultra-High Temperature Resin (UHTR), a polysiloxane-based resin, as a matrix for three candidate reinforcement systems: VDG graphite felt, Carbon-PBI felt, and quartz felt. Virgin and charred samples were produced and analyzed using X-ray computed tomography (XCT) at the University of Southampton’s µ-VIS Imaging Centre. The results aim to establish a framework for cost-effective characterization of low-density flexible ablators (LDFAs), enabling faster material qualification, and supporting future aerospace missions.