Normal and relaxor ferroelectric behavior in the Ba1-xPbx(Ti1-yZry)O-3 solid solutions

Polycrystalline samples of Ba1-xPbx(Ti1-yZry)O-3(BPTZ) with x = 0.025 & 0.1 and 0.10 <= y <= 0.50 have been synthesized by high-temperature solid-state reaction technique. X-ray diffraction reveals the formation of single phase with tetragonal or cubic structure. Dielectric investigations were carried out in the temperature range from 80 to 445 K with frequencies range from 10(2) to 10(6) Hz. A broad dielectric anomaly coupled with the shift of dielectric maxima toward a higher temperature with increasing frequency indicates either a diffuse phase transition or relaxor behavior in some of these ceramics. Whatever lead content, when zirconium is substituted by titanium, T-C and epsilon'r(rmax) decreases while Delta T-m(f) = [T-m(10(6) Hz)-T-m(10(2) Hz)] and tgd increase. The diffuse phase transition parameters were estimated from a linear fit of the modified CurieeWeiss law. A good fit to the VogeleFlcher relation further corroborates suchrelaxor nature. (C) 2016 Elsevier B.V. All rights reserved.