Effect of SrTiO 3 concentration and sintering temperature on microstructure and dielectric constant of Ba 1− xSr xTiO 3

Abstract

The Ba 1− x Sr x TiO 3 materials have received increased attention as one of the most important materials for electroceramic components, such as high dielectric ceramic capacitors, tunable phase shifters and PTCR. In this paper, the effect of SrTiO 3 concentration and sintering temperature on the microstructure and dielectric constant of Ba 1− x Sr x TiO 3 materials at the Curie temperature have been investigated. When Ba 1− x Sr x TiO 3 materials were sintered at 1350 °C, the peak value of the dielectric constant, ϵ max, monotonically decreased with increasing SrTiO 3 concentration. At the sintering temperature of 1400 °C the dielectric constant maximum at the T C increased with an increase in the x value, reaching the highest value at around x=0.4 and then decreased. As sintering temperature increased to 1450 °C, ϵ max increased with increasing SrTiO 3 concentration up to x=0.6. The dielectric properties of Ba 1− x Sr x TiO 3 materials were discussed in terms of SrTiO 3 concentration and microstructure.