Effect of SrTiO3 concentration and sintering temperature on microstructure and dielectric constant of Ba1−xSrxTiO3

The Ba1−xSrxTiO3 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 SrTiO3 concentration and sintering temperature on the microstructure and dielectric constant of Ba1−xSrxTiO3 materials at the Curie temperature have been investigated. When Ba1−xSrxTiO3 materials were sintered at 1350 °C, the peak value of the dielectric constant, ϵmax, monotonically decreased with increasing SrTiO3 concentration. At the sintering temperature of 1400 °C the dielectric constant maximum at the TC 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, ϵmax increased with increasing SrTiO3 concentration up to x=0.6. The dielectric properties of Ba1−xSrxTiO3 materials were discussed in terms of SrTiO3 concentration and microstructure.