Foam-gelcasting preparation of porous SiC ceramic for high-temperature thermal insulation and infrared stealth

• Published in: Rare metals Vol. 42; no. 11; pp. 3829 - 3838
• Main Authors: Liu, Xue-Feng, He, Jiang-Feng, Li, Ya-Ge, Li, Hang, Lei, Wen, Jia, Quan-Li, Zhang, Shao-Wei, Zhang, Hai-Jun
• Format: Journal Article
• Language: English
• Published: Beijing Nonferrous Metals Society of China 01.11.2023; Springer Nature B.V
• Subjects: Biomaterials; Bulk density; Carbon; Chemistry and Materials Science; Controllability; Energy; Extreme environments; Gelcasting; Inert atmospheres; Insulators; Materials Engineering; Materials Science; Materials selection; Metal foils; Metallic Materials; Microspheres; Military equipment; Nanoscale Science and Technology; Operating temperature; Original Article; Physical Chemistry; Porosity; Silicon carbide; Stealth technology; Thermal insulation; Thermal protection; Thermal stability; Wettability; Porous SiC ceramics; Thermal superinsulation; High-temperature infrared camouflage; Foam-gelcasting
• ISSN: 1001-0521; 1867-7185
• DOI: 10.1007/s12598-023-02348-3

Porous SiC ceramics (PSCs) are promising lightweight and efficient thermal insulators that can evade infrared detection by reducing the surface temperature of the protected object, which plays a crucial role in the development of new military equipment. However, the controllable synthesis of PSCs with both hierarchical pore structure and thermal/mechanical stability remains challenging. In this work, such PSCs were prepared by a facile foam-gelcasting/solid-state reaction method, using silicon powders and glucose-derived carbon as starting materials. The favorable dispersibility and wettability of hydrophilic carbon microspheres and the in-situ formed SiC guarantee the highly porous structure (92.8% porosity), comparable bulk density (0.20 g·cm −3 ) and reasonable mechanical property of the product. The designed PSCs performed outstanding high-temperature performance, especially thermal insulation in both oxidizing and inert atmospheres. More importantly, the composite architecture of PSCs and low emissivity layer (Al foil) exhibited desirable infrared stealth property (at a temperature up to 1100 °C), significantly extending the operating temperature range of thermal camouflage material. The unique combination of excellent properties would make PSCs a potential candidate material for future thermal protection and infrared stealth applications in an extreme environment. Graphical abstract