Phase-transformation and low-temperature sintering of WO₃ and B₂O₃ doped zinc titanate ceramics

Zinc titanate ceramics were prepared by conventional mixed-oxide method combined with a semi-chemical processing. The effects of WO₃-B ₂O₃ addition on the low-temperature sintering behavior and phase-transformation of zinc titanate ceramics were studied; and low-temperature sintering mechanism was suggested. The results show that the firing temperature of zinc titanate ceramics can be reduced from 1 100 to below 900 °C by WO₃-B₂O₃ addition. The low-temperature sintering mechanism of WO₃ is different from that of B₂O₃, the former one is believed to be corresponding to the solid phase reaction, while the latter is related to liquid phase sintering mechanism. WO₃ accelerates the decomposition of hexagonal ZnTiO ₃ phase, the reason for which was investigated. The dielectric properties of zinc titanate ceramics were measured at different frequencies, and the results indicate that the main polar behavior varies with the frequency.