Effect of particle size and ZnO addition on microwave dielectric properties of nanocrystalline (Zr < inf > 0.8 < /inf > Sn < inf > 0.2 < /inf > ) TiO < inf > 4 < /inf > ceramics

Abstract

Polycrystalline samples of (Zr0.8Sn0.2)TiO4 have been synthesised by solid state reaction method. The effects of ball milling and the addition of ZnO (1-2.5 wt-%) on the microwave dielectric properties of (Zr0.8Sn0.2)TiO4 ceramics are investigated. As the ball milling time increases, the density of the (Zr0.8Sn0.2)TiO4 ceramics increases. The influence of ZnO as a sintering aid on the sintering temperature of (Zr0.8Sn0.2)TiO4 is also studied. As the weight percentage of ZnO increases, the density increases up to 1.5 wt-% of ZnO and thereafter it starts decreasing. The dielectric constant εr and the product of quality factor Q and resonant frequency fo of TE01δ mode Qxfo) followed the same trend with increasing density, irrespective of whether the density increased with ball milling time or by addition of ZnO. The value of Qxfo is found to increase with increasing grain size. The microwave dielectric constant and the Qxfo values were respectively ranged from 32 to 39.3 and from 32 000 to 49 600 at 10.5 GHz for (Zr0.8Sn0.2)TiO4 ceramics. Furthermore, the influence of the processing parameters on the microwave dielectric properties of Zr0.8Sn0.2) TiO4 is discussed. © 2007 Institute of Materials, Minerals and Mining.