High-Temperature Properties of Ceramic Fibers and Insulations for Thermal Protection of Atmospheric Entry and Hypersonic Cruise Vehicles

Multilayer insulations which will operate in the 500°C to 1000°C tempera ture range are being considered for possible applications on aerospace vehicles subject to convective and radiative heating during atmospheric entry. The in sulations described in this paper consist of ceramic fabrics, insulations, and metal foils quilted together using ceramic thread. As these types of insulations have highly anisotropic properties, the total heat transfer characteristics of these insulations must be determined. Data are presented on the thermal dif fusivity and thermal conductivity of four types of multilayer insulations and are compared to the baseline Advanced Flexible Reusable Surface Insulation (AFRSI) currently used on the Space Shuttle Orbiter. In addition, the high- temperature properties of the fibers used in these multilayer insulations are discussed. The fibers investigated included silica and three types of alumino borosilicate (ABS). Static tension tests were performed at temperatures up to 1200 ° C and the ultimate strain, tensile strength, and tensile modulus of single fibers were determined.