Measurements of complex materials constants of piezoelectric ceramics: Radial vibrational mode of a ceramic disk

An iterative method for characterization of piezoelectric ceramics of a disk in radial vibrational mode has been developed. The complex materials constants (dielectric constants, elastic compliance coefficients and piezoelectric constants) of piezoelectric ceramics with various mechanical quality factor (Q) were accurately determined. An explicit procedure for estimating the appropriate initial values of the complex materials constants for a nonlinear iteration process has been presented. The present nonlinear iterative fitting procedure was carried out for the experimental admittance spectra Y = G + j B for various specimens with moderate (667) or low (29) Q values and the validity of the method was verified.