ON THE NATURE OF THE MECHANICAL RESONANCE ASSOCIATED WITH THE ELECTRICAL RESONANCE OF A POLED PZT65/35 DISK

In this paper we present experimental results concerning the axial mechanical displacements of a partially and fully poled ferroelectric ceramic disc of PZT65/35 composition in the neighborhood of its lowest detectable electrical resonance. The measured displacements are resolved into their flexural and thickness components which are due, respectively, to a recently discovered new electric-to-mechanical coupling phenomenon and conventional piezoelectric coupling. Flexural resonances and a 'thickness' resonance are detected. The frequencies of the former increases with remanent polarization, and the frequency of the latter decreases with remanent polarization. In particular, the nature of the 'thickness' resonance indicates that this resonance is not one-dimensional in character as postulated in many theoretical considerations.