Temperature dependence of the transverse piezoelectric properties in the [001]-poled 0.25Pb(In_1/2Nb_1/2)O₃-0.42Pb(Mg_1/3Nb_2/3)O₃-0.33PbTiO₃single crystal with alternating current treatment

In this work, the transverse piezoelectric properties of the pre-direct current poled (DCP) 0.25Pb(In1/2Nb1/2)O3-0.42Pb(Mg1/3Nb2/3)O3-0.33PbTiO3 (0.25PIN-0.42PMN-0.33PT) single crystals were enhanced by the alternating current treatment (ACT) of 10 kVp/cm (5.8 kVrms/cm), 50 Hz, and 20 cycles. The transverse piezoelectric constant d 31 of -1560 pC/N and electromechanical coupling coefficient k 31 of 0.92 at room temperature were achieved in the DCP-ACT crystal, which were, respectively, 80% and 11% higher than those of the DCP crystal (d 31 = - 870 pC / N, k 31 = 0.83). Meanwhile, the elastic compliance constant S 11 E and dielectric permittivity ϵ 33 T / ϵ 0 of the DCP-ACT crystal were, respectively, 78% and 46% higher than those of the DCP crystal. Based on the temperature dependence of dielectric properties and resonance curves, the d 31, ϵ 33 T / ϵ 0, and S 11 E of the DCP-ACT crystal were higher than those of the DCP crystal in the R phase region. The DCP-ACT crystal also showed a higher TFerro (110 °C) than the DCP crystal (96 °C), which was related to the intermediate phase induced by ACT. The d 31 at Tferro of the DCP-ACT crystal can be -3810 pC/N, which was 2.3 times that of the DCP crystal (-1680 pC/N). In the T phase region, the DCP-ACT crystal presented a high ϵ 33 T / ϵ 0 and attenuated impedance resonance. Moreover, ACT also affected the ferroelectric to paraelectric phase transition. This could be related to the nanoscale heterogeneous polar region induced by ACT, which enhanced the inhomogeneous state in the relaxor-based ferroelectric single crystal. ACT is a potential way for improving the transverse piezoelectric properties of the PIN-PMN-PT single crystal.