Enhanced High-Power Performance in PZT Ceramics through Integration of Defect and Grain-Size Engineering

The stability of the mechanical quality factor (Q_m) is particularly crucial for high-power piezoelectric applications. Acceptor doping has been validated as an important hardening method, but Q_m shows serious degradation at high-power conditions due to the high mobility of oxygen vacancies. Here, an integrated approach based on acceptor doping and a dense fine-grain structure is demonstrated for achieving a strong pinning effect on domain walls, thus leading to a high-power stable Q_m. Mn acceptor doping in Pb_0.9Ba_0.1Zr_0.53Ti_0.47O₃ (PBZT) ceramic results in effective piezoelectric hardening, where the Q_m increases to 800 in a 0.5 wt % Mn-doped PBZT (0.5Mn) sample, increasing by 370% compared to the undoped counterpart. By engineering the grain size of 0.5Mn ceramic, a more stable domain configuration is achieved, resulting in a slower degradation magnitude of Q_m, i.e., at a vibration velocity of 0.5 m/s by 35% and 1.0 m/s by 60%, while that of the counterpart is 45 and 80%. Therefore, high-power Q_m can be effectively improved by combining defect and grain-size engineering, providing a way for developing high-power piezoelectric materials.