The computation of the k factor for lossy materials around resonance

Abstract

An important property of a piezoelectric material for practical applications is its ability to generate and to detect stress waves, i.e. to convert electrical energy into mechanical energy and vice versa. As it is well known, the electromechanical coupling factor k fully characterize this energy conversion under static conditions. In this work we show that the definition of kw as ratio of energies can also be extended to lossy materials (kw); the losses are accounted by considering comlex quantities for the elastic, dielectric and piezoelectric material constants.