Effects of the Sintering Temperature on the Structure and Properties of the Alumina Foamed Ceramics

Alumina foam ceramics reinforced with alumina fibers were prepared with gel-casting. The effects of the sintering temperature on the foam ceramics were investigated. The foam ceramics were composed of α-Al2O3, C-AlPO4, and T-AlPO4 phases. And the mount of T-AlPO4 phase decreased, while the mount of C-AlPO4 phase increased once the sintering temperature exceeded 1180℃ due to the phase transformation of T-AlPO4 to C-AlPO4 phase. The grain average size of the foam ceramic increased obviously with the sintering temperature rise, so did its bulk density. While its open porosity decreased. The compression strength of the foam ceramic continuously increased with the sintering temperature rise from 980 to 1580 °C