Improved piezoelectric properties via mechano-chemical activation in modified PCT ceramics

High-density samarium modified lead calcium titanate ceramics were successfully prepared by using a novel mechano-chemical activation technique, which skips the calcinations steps at an intermediate temperature that is always required in the normal conventional technique. Better densification could be achieved by activation process. XRD study showed single-phase formation with tetragonal structure and microstructural study revealed almost uniform grain size of 1.4 μm. Dielectric study demonstrated sharp peak in dielectric versus temperature plots and slightly low value of the Tc as compared to that observed for samples prepared by conventional technique. The mechanical alloying technique rendered drastic improvement in piezoelectric properties. The ratio of electromechanical anisotropy (kt/kp) was obtained to be ∼62 as compared to 52 in the case of samples by conventional process. Comparison in the structural and electrical properties is discussed in detail for conventional versus mechano-chemical alloying process.