Preparation, Structure, and Electric Properties of the Pb(Lu1/2Nb1/2)O3–Pb(Ni1/3Nb2/3)O3–PbTiO3 Ternary Ferroelectric System Ceramics Near the Morphotropic Phase Boundary

0.30Pb(Lu1/2Nb1/2)O-3-xPb(Ni1/3Nb2/3)O-3-(0.70-x)PbTiO3(PLN-PNN-PT) ceramics with various PNN contents were prepared using a modified two-step columbite precursor method and characterized by X-ray diffraction (XRD), ferroelectric and dielectric measurements. The composition of 0.30PLN-0.31PNN0.39PT exhibits excellent physical properties with d(33) = 366pC/N, Tc = 214 degrees C, epsilon' = 3076, tan delta = 0.0225, Pr = 32.89 mu/cm(2) and Ec = 15.23KV/cm. The values of relaxor factor gamma approaches 2 indicating diffuse character of PLN-PNN-PT ceramic. The dielectric behavior was discussed based on Curie-Weiss Law and Lorentz-type quadratic relationship. A transformation from relaxor ferroelectric to normal ferroelectric was demonstrated with PT content increasing in this ternary system. (C) 2017 Elsevier B.V. All rights reserved.