Microstructural design for mechanical and electrical properties of Spark Plasma Sintered Al2O3-SiC nanocomposites

Abstract

[EN] Al2O3-17 vol.% SiC nanocomposites were prepared by powder mixture of submicrosized alpha-Al2O3, nanosized gamma-Al2O3 and different nanosized beta-SiC. Materials were sintered by spark plasma sintering (SPS) technique at two temperatures (1400-1550 degrees 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 Al2O3 matrix grains and/or at the Al2O3 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 Omega cm) or insulating (10(8) Omega cm) materials while the chemical composition is similar. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.