High-power piezoelectric behavior of acceptor-doped 〈001〉 and 〈111〉 textured piezoelectric ceramics

Abstract

Piezoelectric ceramics with high piezoelectric co-efficient, d₃₃, and mechanical quality factor, Q_m, are required in high-power applications. 〈001〉 and 〈111〉 textured Pb(In_1/2Nb_1/2)O₃–Pb(Mg_1/3Nb_2/3)O₃–PbTiO₃ ceramics were fabricated using templated grain growth method and their high-power electromechanical properties were characterized. It is shown that 〈001〉 textured ceramics possess higher d₃₃ compared to random and 〈111〉 textured counterparts, while the Q_m is strongly enhanced in 〈111〉 textured ceramics due to less favored polarization rotation. MnO₂ doping is shown to further improve the Q_m values for both 〈001〉 and 〈111〉 textured ceramics because of the restricted polarization switching induced by the defect dipole. Doped 〈001〉 textured ceramics can exhibit the high d₃₃ and moderate Q_m (d₃₃ = 725 pC N⁻¹, Q_m = 716) in comparison with 〈111〉 textured ceramics exhibiting low d₃₃ and high Q_m (d₃₃ = 350 pC N⁻¹, Q_m = 1495). Owing to the combinatory soft and hard piezoelectric properties, the doped 〈001〉 textured ceramics exhibit 1.5× higher vibration velocity (∼0.90 m s⁻¹) in comparison with commercial hard PZTs. Interestingly, a slightly higher vibration velocity (∼0.94 m s⁻¹) can be obtained in doped 〈111〉 textured ceramics, which is mainly attributed to the high Q_m and low elastic compliance s₁₁. These results demonstrate the promise of textured piezoelectric ceramics for high-power applications.