Graphene nanoplatelet/silicon nitride composites with high electrical conductivity Original Research Article

Silicon nitride (Si3N4) processed with up to 25 vol.% of graphene nanoplatelets (GNPs) gives conductive composites with the highest electrical conductivity (40 Scm−1) reported for these ceramics with added conductive particles. During compaction and pressure-assisted densification of the composites in the spark plasma sintering (SPS), a preferred orientation of GNPs occurs. Consequently, the electrical conductivity measured along the direction perpendicular to the SPS pressing axis is more than one order of magnitude higher than the one measured along the parallel direction.