Investigation of phase structure and electrical properties of PMN-PSN-PNN–PZT ceramics with different PNN content

Piezoelectric ceramics, as an essential electronic material, are widely used in various actuators and ultrasonic transducers. In this study, piezoceramics in the formula Pb_0.94Sr_0.04Ba_0.02(Mg_1/3Nb_2/3)_0.025(Sb_1/2Nb_1/2)_0.025(Ni_1/3Nb_2/3)_x(Zr_0.48Ti_0.52)_0.95−xO₃ + 0.2wt%Li₂CO₃, where x = 0.21 − 0.17(abbreviated as PMN-PSN-xPNN-(0.95-x)PZT) were investigated. By changing the PNN content from 0.21 to 0.17, high piezoelectric coefficient d₃₃ from 860 pC/N to 700 pC/N, high Curie temperature T_c from 137 ℃ to 168 ℃ were obtained. All the ceramics show excellent electrical properties. It is 15 − 20% better than PNN-PZT or doped PNN-PZT piezoelectric ceramics in certain aspects. What’s more, the ceramics also carry extraordinary electromechanical coupling factor k_p (from 67 to 73%). Hence, this is an excellent candidate for actuators and transducers applications.