Investigation on dielectric and piezoelectric characterization of PLSZT-BT ceramics

In this paper, the ceramic compositions (1-x)Pb1-w-yLawSry(ZrzTi1-z)((1-w/4)) O3-xBaTiO3, where x = 0.15, 0.25, 0.35 and 0.45, fabricated through solid state reaction method were investigated for phase formation, microstructure, density, dielectric and piezoelectric properties. The combination of the two perovskite structured stoichiometric compositions (i.e., isovalent Sr2+ modified PLZT and BaTiO3) indicated that tetragonality enhanced further due to BaTiO3 concentration in PLSZT lattice. The BaTiO3 in PLSZT ceramics were homogeneously distributed within the two perovskite structured solid solutions. The dielectric characterization indicated that epsilon(RT) enhanced while tan delta(RT) and T-c decreased with increasing BT additions into PLSZT perovskite. The maximum epsilon(RT) = 2986 and epsilon(Tc) = 21468 were found in 0.55PLSZT-0.45BT ceramic system. The piezoelectric properties were influenced by both BaTiO3 and Sr2+ modified PLZT perovskite. The influence of BT modified PLSZT ceramics showed significant variations that has been discussed. The piezoelectric properties remarkably enhanced with maximum (k(p) = 0.541 and d(33) = 518 pC/N) values in the 0.55PLSZT-0.45BT composition and thus, could be a promising candidate among this series for possible capacitor, sensor and actuator applications.