The effect of sintering temperature on phase, microstructure and properties of Sr5Nb4TiO17

Abstract

Ceramics with layered perovskite structures are widely used as microwave dielectric components in the telecommunication industry. The potential of Sr5Nb4TiO17 as a possible Pb-and Bi-free alternative for microwave applications was investigated. Sr5Nb 4TiO17 was prepared by mixed oxide route. Calcined and sintered samples were characterized by X-ray diffraction and scanning electron microscopy. Samples sintered at temperatures ≤1400°C comprised mainly Sr5Nb4TiO17 along with a small amount of Sr2Nb2O7 as a second phase. Single phase dense Sr5Nb4TiO17 with relatively good electrical properties formed at 1450°C whereas Sr6Nb4Ti 2O20 formed as second phase at temperatures ≥1500°C. SEM showed an increase in the grain size and variation in grain morphology with increase in the sintering temperature. Further work is underway to optimize the processing and hence the properties of Sr5Nb 4TiO17. © 2010 IOP Publishing Ltd.