Shear-Mode Piezoelectric Properties of KNbO_3-Based Ferroelectric Ceramics

摘要

Potassium niobate, KNbO_3, (KN)-based ceramics were prepared by a modified conventional ceramic fabrication process to characterize their piezoelectric properties. The KN-MnCO_3 0.1 wt% (KN-Mn0.1) ceramic used in this study showed a high density ratio >96% and a high resistivity, p, of about 10~(13)Ω·cm without deliquescent properties. The shear mode of the KN-Mn0.1 ceramic showed excellent resonance and antiresonance characteristics with tiny spurious peaks upon optimization of the sample dimensions. The electromechanical coupling factor, k_(15), and piezoelectric strain constant, d_(15), of KN-Mn0.1 showed relatively large values of 0.55 and 207 pC/N, respectively. The shear-mode vibration of KN-based ceramics appears to be a very promising candidate for actuators and high-power applications.