Estimation of material parameters of lossy 1-3 piezocomposite plates by non-linear regression analysis

A method to estimate the material parameters of 1-3 piezocomposites by non-linear regression analysis is presented. Experimentally measured electrical impedance data are least-squares fitted to a theoretical expression which accounts for the internal losses of a piezocomposite plate resonator vibrating in the thickness-mode. The process converges rapidly and the estimated values of the material parameters are comparable with that obtained from the constituent relations of 1-3 piezocomposites. The advantage of this method is that it can be used to estimate the material parameters of lossy resonators whose characteristic frequencies cannot be determined accurately. (C) 1999 Academic Press.