Processing of low-density alumina foam

A novel method for synthesizing low-density alumina foam has been developed. The alumina foam with 98.5% porosity was synthesized by an unconventional route from an aqueous aluminum nitrate–sucrose solution. The resin formed by heating this solution underwent foaming and set into solid green foam, which was sintered at 1873 K. The thermogram of the green foam showed mass loss in four stages. The foam exhibited interconnected porous network with window size in the range 103–226 and 167–311 μm for foams sintered at 1223 and 1873 K, respectively. The alumina foam sintered at 1223 K exhibited gamma phase and that sintered at 1873 K exhibited alpha phase.