Microstructure and dielectric properties of BaxSr1−xTiO3 ceramics

The crystalline structure and dielectric properties of BaxSr1−xTiO3 ceramics with x = 0.45, 0.5, 0.6, 0.65, 0.8, 0.9 were investigated. The a- and c-axis lattice constants of BaxSr1−xTiO3 ceramics were calculated and it is found that the crystal structures are tetragonal phase when x ≥ 0.65 at room temperature. The Curie-Weiss temperature (T0) is always lower than Curie temperature (TC) and the linear relation between the Curie temperature and the stoichiometric percentage of barium can be observed and expressed as TC (°C) = −195.0 + 322.2x. The values of coercive electric field (EC) and remanent polarization (Pr) increase as Ba/Sr ratio of BaxSr1−xTiO3 ceramics increases except for x ≤ 0.5, which are due to the decrease in grain size and the difference between the radius of Ba2+ and that of Sr2+.