Preparation and Characterization of New Pb(Yb_1/2Nb_1/2)O₃-Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃ Ternary Piezo-/Ferroelectric Crystals

Abstract

Piezo-/ferroelectric crystals of a new Pb(Yb1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 ternary solid solution system with the dimensions of 30 × 30 × 12 mm3 have been grown by the top-seeded solution growth method for the first time. The crystal structure is analyzed by means of X-ray diffraction at various temperature. The composition of the grown crystals is found to be near the ternary morphotropic phase boundary. The Curie temperature TC reaches 205 °C. The piezoelectric coefficient d33 and the longitudinal electromechanical coupling factor k33 are found to be 1800 pC/N and 90%, respectively. A remanent polarization Pr of 27.8 μC/cm2 is displayed with a coercive field Ec of about 7 kV/cm. These results show that the PYMNT crystals exhibit a higher TC and a larger coercive field than the binary PMN-PT piezocrystals, making this material a promising candidate for high-power electromechanical transducers that can operate in a wider temperature range.