Phase transitions of low-temperature sintering tungsten-doped ZnO-TiO2 ceramics

Abstract

WO3-doped zinc titanate ceramics were prepared by conventional mixed-oxide method combined with a chemical processing. The effects of WO3 addition on the low-temperature sintering behavior, phase transition and dielectric properties of zinc titanate ceramics were investigated. The results show that the densification temperature of ZnTiO3 ceramics can be reduced from 1150 to 900 °C with WO3 addition and chemical processing. Small amount of WO3 (<1.00wt %) accelerated the decomposition of hexagonal ZnTiO3 phase to cubic Zn2TiO4 phase, while excessive addition (for example, 3.00wt %) restrained the decomposition. At the same time, the phase transition temperature from hexagonal ZnTiO3 phase to cubic Zn2TiO4 is lowered by adding WO3. WO3 addition affects the dielectric properties of ceramics. The dielectric properties of WO3-doped zinc titanate ceramics were measured at different frequencies. The results showed the decreasing tendency with the increasing measuring frequencies for both the dielectric constants and the loss tangents, and there existed the best dielectric properties for 1.0% WO3-doped ceramics.