Fabrication of Infrared Opacifiers Loaded Al2O3 Aerogel-SiO2 Fiber Mat Composites with High Thermal Resistance

Abstract

The infrared opacifiers loaded Al2O3 aerogel-SiO2 fiber mat composites were fabricated by the sol–gel process. The effects of the content of the TiO2 and SiC particles on thermal insulation performance of the Al2O3 aerogel-SiO2 fiber mat composites were studied. The results showed that the optimum doping content of TiO2 and SiC for Al2O3 aerogel-SiO2 fiber mat composites were 10[Formula: see text]mol.% and 0.5[Formula: see text]mol.%, respectively. The optimum TiO2-Al2O3 aerogel-SiO2 fiber mat composite had the low thermal conductivity of 0.021[Formula: see text]W/(m[Formula: see text][Formula: see text][Formula: see text]K) at 35∘C and 0.031[Formula: see text]W/(m[Formula: see text][Formula: see text][Formula: see text]K) at 600∘C. Meanwhile, the SiC-Al2O3 aerogel-SiO2 fiber mat composite also had the low thermal conductivity of 0.022[Formula: see text]W/(m[Formula: see text][Formula: see text][Formula: see text]K) at 35∘C and 0.025[Formula: see text]W/(m[Formula: see text][Formula: see text][Formula: see text]K) at 600∘C.