Processing and Property Evaluation of Alumina Aerogel Based Ceramic Nanocomposites

Aerogels are sol-gel derived mesoporous materials with low apparent density and large specific surface areas. The mechanical property evaluation of pulsed electric current sintered (PECS) alumina and its composite aerogels with nanosized metallic dispersions is an area of interest. In the present work alumina, alumina-copper, alumina-nickel, alumina-cobalt and alumina-tungsten aerogels have been synthesized by super critical drying of respective the sols. The samples were pre-calcined under controlled sintering conditions and pulsed electric current sintered at two different temperatures: (1) at a lower sintering temperature with short residence time (1250°C for 5min) and (2) at a high temperature with prolonged soaking time (1450°C for 30 min) and their mechanical properties were evaluated.