Superior temperature stability of electromechanical properties and resonant frequency in PYN-PZT piezoelectric ceramics

In this study, the Pb(Yb_1/2Nb_1/2)O₃ (PYN) relaxor with high Curie temperature (T_C ∼300 °C) was incorporated into PbZrO₃-PbTiO₃ (PZ-PT) ceramics to form 0.1PYN-(1-x)PZ-xPT ternary ceramics, and their phase compositions were systematically investigated, providing the more detailed phase diagrams, dielectric, piezoelectric, and ferroelectric properties. Excellent piezoelectric performance (d₃₃ ∼ 450 pC/N, d₃₃* ∼714 pm/V), with high coercive field (E_C ∼17.5 kV/cm) and T_C (∼398 °C) were simultaneously achieved in the 0.1PYN-0.41PZ-0.49PT composition near the morphotropic phase boundary (MPB). The value of d₃₃ × E_C, which exhibits higher than commercial PZT ceramics, indicates its suitability for high-field excitation devices. Additionally, the temperature stability of the resonant frequency (f_r) is qualitatively studied by analyzing the main factors influencing f_r from a theoretical perspective. Superior stability is achieved in the 0.1PYN-0.38PZ-0.52PT composition (T_C ∼ 405 °C) with tetragonal phase, and the temperature coefficient of resonant frequency (Δf_r /f_{r 25 °C}) remains within 0.5% up to 300 °C, far outperformance than previous reports.