Anti-ablation and insulation integrated gradient quartz fiber needle felt reinforced SiO₂ ceramic/aerogel composite for thermal protection

Amidst the rigorous thermal challenges faced by hypersonic vehicles, this study introduces a quartz fiber needle felt-reinforced SiO₂ ceramic/aerogel (QF-SA) composite, demonstrating exceptional thermal protection capabilities. Under a quartz lamp, the composite maintained surface temperatures at 800 °C after an initial spike to 1000 °C, with backing plate temperatures peaking at 232 °C after 1000 s for the QF-SA1 variant. Its thermal conductivity, which ranges from 0.022 to 0.042 W/m·K, offers optimized insulation. Laser ablation tests at 3 kW for 9s revealed outstanding durability, with mass and linear ablation rates of 0.0068 ± 0.0002 g/s and 1.5 ± 0.1 mm/s for QF-SA3, respectively—45.6 % and 31.9 % lower than those of QF-A. These results highlight the QF-SA composites potential for high-temperature aerospace applications, indicating a path forward for lightweight, high-performance thermal protection systems. Future work will focus on refining fabrication techniques to achieve optimal performance and address economic constraints.