CHARACTERIZATION OF MECHANICAL VIBRATION DAMPING BY PIEZOELECTRIC MATERIALS

摘要

Piezoelectric materials (piezo-materials) convert mechanical energy into electrical energy via the mechanism of piezoelectricity, and this electrical energy may be dissipated through a connected load resistance. The energy dissipation through this mechanism is termed piezo-damping. New models based on this energy conversion and dissipation have been proposed to characterize the damping behaviour of the piezo-materials. An equivalent electrical circuit model is put forward to determine the required load resistance, and a mechanical spring-dashpot model is used to describe the damping capacity of the piezo-materials. Equations were derived to predict optimal resistance load, maximum damping ratio and the shift of the resonance frequency. A two-degree-of-freedom (2-DOF) experimental set-up was developed to test the validity of the models. The experimental results agree very well with the theoretical predictions. The piezo-damping mechanism exhibits potentially a high damping capacity. (C) 1996 Academic Press Limited [References: 20]