Electric Conductive Si3N4/TiN Composite Ceramic Manufactured by Liquid-Qhase Sintering

Abstract

Si3N4 based electric conductive ceramics were fabricated by pressureless liquid phase sintering with La2O3-AlN and TiN as sintering and conductive additives. The Si3N4 powder was synthesized by SHS (self-propagation high-temperature synthesis) method. The bulk density, mechanical properties and electrical conductivity of the sintered samples were studied. Microstructure and phase composition were analyzed by SEM and XRD. The results show that the density of the samples is above 96%. The sintered samples consist of β-Sialon and the conductive phase. β-Sialon grains shows elongated and the conductive phase granular which formed electric conductive network. The sintered samples have good mechanical properties and its electric resistivity is from 1012 Ω•cm above drop to 1 Ω•cm below.