Effect of Zr4+ on piezoelectric, dielectric and ferroelectric properties of barium calcium titanate lead-free ceramics

[Formula: see text][Formula: see text]([Formula: see text][Formula: see text][Formula: see text](BCTZ) ceramics with [Formula: see text] 0.05, 0.10, 0.15, 0.20, 0.25, 0.30 were prepared by the solid-state reaction method. Calcination of the powders was carried out at 1100 [Formula: see text]C for 4 h and the green pellets were sintered at 1400 [Formula: see text]C for 2 h. X-ray diffraction patterns of the sintered pellets showed tetragonal splitting up to [Formula: see text] 0.10 while the mixture of the rhombohedral/cubic phase appeared at higher ZrO 2 concentrations. Maximum piezoelectric charge constant [Formula: see text] 510 pC/N and strain ([Formula: see text] 0.103%) were measured for BCT doped by 0.10 mol ZrO 2 . Dielectric constant, remnant polarization and saturation polarization also found maxima for this composition. The Curie temperature ([Formula: see text] of the compositions decreased with increase in ZrO 2 concentration and reached 98 [Formula: see text]C, 87 [Formula: see text]C and 36 [Formula: see text]C at [Formula: see text] 0.05, 0.10, 0.15 mol, respectively. The remaining compositions have [Formula: see text] below the room temperature; therefore, they can be used for subzero/cryogenic applications. The scanning electron microscopy study revealed an increase in grain size with increase in ZrO 2 concentration and confirmed the complete solubility of ZrO 2 in the crystal lattice. Overall, low ZrO 2 -doped BCT compositions with high [Formula: see text] could be suitable for low temperature (<80 [Formula: see text]C) applications.