Refined Position of the Morphotropic Phase Boundary and Compositional Search of Pb(Mg1/3Nb2/3)O3-PbZrO3-PbTiO3 Ceramics for Piezoelectric Applications

The morphotropic phase boundary (MPB) for the PMNZT series of high-density ceramics (xPb(Mg1/3Nb2/3)O3-yPbZrO3-zPbTiO3; x=0.1-0.2, y=0.400-0.486, z=0.395-0.477) is relocated based on analyses of the dielectric, piezoelectric and ferroelectric properties of incremental compositions. The PMNZT ceramics, fabricated by the columbite route, exhibit a single-phase perovskite structure. The refined MPB line is shifted toward the PbTiO3 (PT) side in the ternary field by approximately 2.4 mol% from the position reported in the literature and the pinpoint composition for piezoelectric applications is further shifted toward the PT side by approximately 1.2 mol% from the obtained MPB line. The PMNZT 14.2/41.6/44.2 (100x/100y/100z) composition near the MPB line is shown to have properties suitable for practical applications.