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

Relaxor based ternary (0.60 - x) Pb(In1/2Nb1/2) O-3-0.40Pb(Mg1/3Nb2/3)-xPbTiO(3) ((0.60 - x) PIN-0.40PMNxPT) polycrystalline ceramics were synthesized by twostep columbite precursor method. The effects of PIN/PT content on phase structure, microstructure, density, and dielectric, piezoelectric, ferroelectric and pyroelectric properties of the ternary ceramics were systematically investigated. A morphotropic phase boundary (MPB) near x = 0.34 was identified by X-ray diffraction and further confirmed by their respective electrical properties. Piezoelectric, ferroelectric and pyroelectric properties were enhanced for compositions near the MPB. The 0.26PIN0.40PMN- 0.34PT ceramics show optimum electrical properties: piezoelectric coefficient d(33) = 505 pC/N, planar electromechanical coupling factor k(p) = 62.5 %, remnant polarization P-r = 32.1 mu C/cm(2), coercive field E-c = 8.8 kV/cm, and room temperature pyroelectric coefficient p = 0.050 mu C/cm(2) degrees C. In addition, the rhombohedral-tetragonal phase transition temperature T-rt and Curie temperature T-c of the ternary ceramics were identified by the temperature dependence of dielectric and pyroelectric measurements, which are much higher than those of binary PMN-PT ceramics, indicating the expanded temperature usage range of the ternary ceramics. The results show that this ternary system is a promising candidate for electromechanical applications with high performance and wide temperature usage range.