Synthesis and characterization of PB free piezoelectric ceramics-barium zirconate titanate-barium calcium titanate

Abstract

Lead free piezoelectric ceramics with high piezoelectric coefficients are in great demand for sensor and actuator applications. Synthesis and characterization study of one such lead free system, barium zirconate titanate - barium calcium titanate [xBZT-(1-x)BCT] (x = 0.5), via sol-gel method have been carried out. X-ray diffraction (XRD) and transmission electron microscopy (TEM) confirmed the formation of single phase BZT-BCT nanoparticles ( < 50 nm). The as-synthesized powders were calcined at 1000°C and the powders were pressed into cylindrical pellets. Solid-state sintering of the green pellets at 1550°C for 2 hrs resulted in single phase perovskite structure. Hysteresis loops were obtained which indicates the ferroelectric nature of BZT-BCT. The bulk ceramic samples with the highest sintered density (∼93%) were subjected to electrical poling and the piezoelectric properties (d33, k p, & εr) were measured. The structure and piezoelectric properties were investigated and correlated for the given composition of the BZT-BCT system.