Study of Structure and Dielectric Properties of (Ba1―xCax)(Ti0.82Zr0.18)O3 Ceramics

(Ba1―xCax)(Ti0.82Zr0.18)O3(BCZT, 0≤x≤0.26) ceramics was prepared by a solid phase reaction. The effect of Ca2+ doping on the microstructure and dielectric properties of the ceramics was studied. Results showed that the solid solubility lay around x=0.16 for BCZT ceramics while the second phase was observed. The value of c/a changed as the U―type curve with the variation of the Ca2+, and the minimum of the c/a was 1.00276 at x=0.06. It was found that Ca2+ ion substitution can be almost incorporated into the A site by the calculation of the tolerance factor and lattice constant. With increasing Ca2+ ion content, the grain size was decreased. The Curie temperature was shifted to low temperature, and the εr―T peak was decreased and broaden. The relaxor characteristics were obtained while Ca2+ ion content was further increased.