Electrical Excitation of Flexural Mechanical Resonances in Symmetrically Electroded Piezoelectric and Ferroelectric Specimens

摘要

A clear understanding of the relationship of mechanical and acoustical excitation to electrical output of piezoelectric materials is important in the design of large-area acoustic sensors. Chen(I1 Nuovo Cimento 2 D, 1145-1155 (1983)) has reported on electrical excitation of flexural mechanical resonances that are not accompanied by detectable electrical disturbances in the ac drive circuits in a number of different specimens such as X- and Z-cut quartz, Z-cut LiNb03, ADP, PZTs, BaTi03, and PLZTs. These observations have raised questions about the understanding of electromechanical interactions. Speculations about the cause of the resonances include the possibility of incompleteness of the constitutive equations of piezoelectricity, surface polarization phenomena, and simple couplings due to slight structural asymmetries. Keywords: Piezoelectric; Ferroelectric; Electromechanical resonance; Structural asymmetry; Induced body couple; Reprints. (mjm)