Optimizing Sintering Temperature for Enhanced Piezoelectric Performance in PMT-PNT-PZT Ceramics

0.006Pb(Mn1/3Ta2/3)O3-0.114Pb(Ni1/3Ta2/3)O3-0.43PbZrO3-0.45PbTiO3 lead-based ceramics (PMT-PNT-PZT) were synthesized via the solid-state reaction at different sintering temperatures to study their effects on phase structure, microstructure, and electrical properties. The maximum mechanical quality factor (Qm) and relative permittivity (εr) were achieved at the sintering temperature of 1200 °C. The piezoelectric constant d33 of 400 pC/N was obtained at 1180 °C, which is attributed to the high grain density and the significant contribution from the remanent polarization and permittivity product (Prεr = 39115 μC/cm2). Compared with commercial PZT4 ceramics, the present composition sintered at 1180 °C exhibits an optimal balance between d33 and Qm, together with the superior figure of merit (FOM = 2.04 × 10⁵ pC/N). Furthermore, it demonstrates excellent temperature stability in electromechanical coupling performance.