a b s t r a c tAl 2 O 3 -17 vol.% SiC nanocomposites were prepared by powder mixture of submicrosized ␣-Al 2 O 3 , nanosized ␥-Al 2 O 3 and different nanosized -SiC. Materials were sintered by spark plasma sintering (SPS) technique at two temperatures (1400-1550• C) and their electrical conductivity and mechanical properties were investigated. High-density composites have been achieved even at the lowest sintering temperatures and the microstructure characterization shows SiC particles located both within the Al 2 O 3 matrix grains and/or at the Al 2 O 3 grain boundaries.It has been demonstrated that microstructure tailoring is possible by suitable selection of starting materials and fast sintering by SPS. Accurate design of nanocomposites microstructures allows obtaining moderately conductive (<100 cm) or insulating (10 8 cm) materials while the chemical composition is similar.Crown