Enhanced piezoelectric properties in (Ba1-xCax)(Ti0.90Sn0.10)O3-0.08Dy2O3 lead-free ceramics

Highlights: • MPB exists in the BCTSD ceramics with x = 0.06–0.10. • BCTSD ceramics exhibit typical diffuse phase transition behavior, which is not sensitive to the amount of Ca²⁺ ions. • Remarkable improvement on piezoelectric properties (d₃₃ = 675 pC/N, k_p = 55%) were achieved at x = 0.06. - Abstract: (Ba_1-xCa_x)(Ti_0.90Sn_0.10)O₃-0.08Dy₂O₃ ceramics (BCTSD-x, x = 0.02–0.10) were fabricated by conventional solid state sintering method. The effect of Ca²⁺ ions addition on the phase structure, microstructure, and electric properties of ceramics were studied. X-ray diffraction analysis reveals the replacement of Ba²⁺ ions in the perovskite structure by Ca²⁺ ions. Rhombohedral phase and tetragonal phase coexist in the composition with x = 0.06–0.10. Both d₃₃ and K_p of the ceramics increase with increasing Ca concentration, and attain maximum values of 675 pC/N and 55.0%, respectively, for x = 0.06. All the ceramics present typical diffuse phase transition behavior, and the feature is not sensitive to the amount of Ca²⁺ ions.