Electrically conductive alumina-carbon nanocomposites prepared by Spark Plasma Sintering

Carbon nanotubes (CNTs) and carbon black were added to alumina to convert it into a good electrical conductor. Alumina-CNT and alumina-carbon black nanocomposites were fabricated by Spark Plasma Sintering (SPS). The electrical conductivity of alumina-CNT nanocomposites was found to be four times higher as compared to alumina-carbon black nanocomposites due to the fibrous nature and high aspect ratio of CNTs. The electrical conductivity of alumina-CNT nanocomposite increased with increasing grain size due to increasing density of CNTs at the grain boundaries. This effect was not observed for alumina-carbon black nanocomposite due to the particulate geometry of the carbon black. (C) 2009 Elsevier Ltd. All rights reserved.