Enhancing high power performances of Pb(Mn_1/3Nb_2/3)O₃–Pb(Zr,Ti)O₃ ceramics by Bi(Ni_1/2Ti_1/2)O₃ modification

High power piezoelectric ceramics 0.04Bi(Ni_1/2Ti_1/2)O₃-xPb(Mn_1/3Nb_2/3)O₃-(0.96-x)Pb(Zr_yTi_1-y)O₃ (BNT-xPMnN-PZ_yT) with various contents of PMnN from 0 to 12 mol% (keep y = 0.50) and Zr/Ti ratio gradually increasing from 48/52 to 52/48 (keep x = 0.06) were prepared by solid-state method. X-ray diffraction (XRD) results show a single phase of polycrystalline perovskite and indicate that the phase structure transforms from tetragonal phase to rhombohedral with x and y increasing. The optimal comprehensive properties of BNT-xPMnN-PZ_yT ceramic, d₃₃ (355 pC/N), k_p (0.58), ε_r (1512), tanδ (0.40%), T_c (336 °C) and Q_m (2010), are obtained at x = 0.06 and y = 0.50, which are apparently superior to typical or commercial Pb(Zr,Ti)O₃ (PZT) based power ceramics. Within the range from room temperature to 200 °C, the variation of electric-field induced strains is less than 8.3%, indicating its good temperature stability. The maximum vibration velocity of the ceramic at temperature rise of 20 °C is measured to be 0.92 m/s, which is about 2 times higher than that of commercial hard PZT ceramics, suggesting the BNT-xPMnN-PZ_yT ceramic is a competitive and potential candidate for power piezoelectric transduction and actuation applications.