Abstract:Due to severe radiation heat transfer at high temperature, the thermal conductivity of hard carbon felt is high. In this paper, the layered hard alumina fiber insulation felt was derived successfully by vacuum impregnation and carbonization process, from alumina fiber as the main material, graphite foil as radiation shielding layer, phenolic resin as impregnant. The materials were tested and analyzed on microstructure, mechanical properties and thermal insulation properties. The results show that the sample has a certain rigidity due to the role of armored" and "anchoring" effect which is produced by carbonization of phenolic resin; The tensile strength of the sample with the 35% concentration of phenolic resin was 70KPa and the thermal conductivity is 0.18 W/m.K at 1000 degrees; In the thermal insulation testing, keeping the hot surface of the sample with thickness of 10mm at constant temperature of 1000 degrees, the temperature of its cold face at steady state is only 640 degrees, which is 200 degrees lower than the temperature, if a commercial carbon felt were used in the same testing. The material has excellent performance and wide application prospect.