Intergranular alumina–SiC micro-nanocomposites sintered by spark plasma sintering

Alumina–5 vol% SiC micro-nanocomposites with almost completely intergranular microstructure were produced by spark plasma sintering (SPS). Before sintering, well dispersed slurries were obtained by ball-milling of powders using an electrosteric dispersant in aqueous media. High density composites could be achieved at lower sintering temperatures by SPS, as compared with hot pressing (HP) sintering process. Microstructure studies show that the nano-SiC particles were mainly located at the alumina grain boundaries.