5H-3 Material Parameter Identification of Piezoelectric Transducers Including the Whole Assembly

In many applications of piezoelectric transducers, the whole assembly including adaption and protection layers as well as mounting is of decisive influence on the electromechanical coupling properties of the actual sensor or actuator under consideration. In order to be able to perform realistic numerical computations of technical systems, excited by a piezoelectric transducer, one has to precisely know the material parameters of a piezoelectric material including the whole transducer assembly. Therewith, we propose a numerical scheme that fully takes into account assembly influences by using finite element simulations of the coupled systems modeling the whole transducer setup including components such as adaption layers as well as mounting. In an inverse scheme for identifying the material parameters, the results of these coupled simulations are automatically fitted to electric impedance measurements by means of a regularized gradient method. This approach also enables to identify unknown material properties of the surrounding non-piezoelectric materials. The applicability of our inverse scheme will be demonstrated by the determination of the material parameters of all components of a Langevin type piezoelectric transducer used in ultrasonic cleaning