Aging Behavior and Mechanical Properties of 0.69Pb(Mg_1/3Nb_2/3)O₃-0.31PbTiO₃Ceramics

Abstract

0.69Pb(Mg 1/3 Nb 2/3 )O 3 -0.31PbTiO 3 (0.69PMN-0.31PT) ceramics were prepared by the solid-state reaction method via the columbite precursor route, which exhibit phasepure perovskite structure with the morphotropic phase boundary (MPB) composition and excellent electrical properties, and are appropriate for further research. Dielectric aging behavior of the 0.69PMN-0.31PT ceramics exhibits a linear decrease dependence on the logarithm of time, proving partly its relaxor ferroelectric characteristic and correlates with microcompositional inhomogeneity. The electrical properties of the 0.69PMN-0.31PT ceramics decrease greatly above the depolarization temperature, being 120 • C, whereas they exhibit excellent time stabilization. Mechanical properties of the 0.69PMN-0.31PT ceramics are improved apparently after coating Ag electrode and poling, which relate to the contributions of electrode status and domain switching. The major failure mechanism is transgranular fracture in the compression fracture samples and intergranular fracture in the bending fracture samples, respectively, determined by SEM observation.

Phase transitional behavior and electrical properties of Pb(In1/2Nb1/2)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3 ternary ceramics

“…The E c of the ceramics containing PIN is higher than that in PMN-PT ceramics and the P r is also much higher. Hence PIN-PMN-PT is a harder material compared to PMN-PT, consistent with the higher Curie temperatures [17,18].…”

“…With increasing PT content, the T rt decreases slightly from 128°C at x = 0.30 to 117°C at x = 0.34, while the Curie temperature T c increases obviously from 186°C at x = 0.30 to 230°C at x = 0.40. Compared with binary PMN-PT ceramics [17,18], both T rt and T c have been remarkably improved by adding PIN. Figure 6 displays the values of piezoelectric constant d 33 , planar electromechanical coupling factor k p , and the mechanical quality factor Q m as a function of PT content for the PIN-PMN-PT ceramics.…”