Preparation of flexible ultra-fine Al2O3 fiber mats via the solution blowing method

Alumina fiber and fiber mat are important ceramic materials, which can be used in many fields including high temperature filtration, thermal insulation and catalyst support. This article demonstrates that alumina fiber mats can be obtained by the solution blowing process combined with the sol-gel method and a subsequent thermal treatment process. During the solution blowing process, the as-spun composite fibers were formed after the solvent evaporation and drawing of the gas flow. These fibers successfully converted into γ-Al2O3 and α-Al2O3 under the thermal treatment in air at 900 °C and 1100 °C. Diameter of as-spun fiber with the range from 2 μm to 5 μm was influenced obviously by adjusting the spinning parameters, such as gel viscosity and highly pressure gas flow. In addition, the resulting alumina fiber mat performed an excellent flexibility, which was significant to the high temperature filtration and other applications.