A systematic analysis of the radial resonance frequency spectra of the PZT-based (Zr/Ti = 52/48) piezoceramic thin disks

In this paper, both the 1D radial mode and the equivalent circuit of a piezoceramic disk resonator were theoretically analyzed based on IEEE standards. And then, the radial resonance frequency spectra of the PZT-based (Nb/Ce co-doped Pb(Zr_0.52Ti_0.48)O₃, abbreviated as PZT-NC) piezoceramic circular disks were measured by an impedance analyzer. A set of resonance frequency spectra including six electrical parameters: Z, R, X, Y, G, and B, were used for making a value distinction between three possible resonance frequencies, and between three possible antiresonance frequencies. A new-form Nyquist diagram was depicted to describe the position relations of these characteristic frequencies. Such a complete resonance frequency spectrum was used to perform the accurate calculation of some material constants and electromechanical coupling parameters for the PZT-NC piezoceramics. Further, the frequency dependence of the AC conductive behavior of the specimen was characterized by the complex impedance measurement. The values of AC conductivity at resonance/antiresonance were deduced from the equivalent circuit parameters. Moreover, the Van Dyke circuit model was assigned to each element contribution and the simulated curves showed a nice fitting with the experimental results. Finally, an additional impedance analysis associated with resonance frequency calculation revealed a complicated coupled vibration mode existing in the annular disk specimen.