Electromechanical properties and actuation capability of an extension mode piezoelectric fiber composite actuator with cylindrically periodic microstructure

摘要

An extension mode piezoelectric fiber composite (PFC) actuator with cylindrically periodic microstructure is presented in this work especially for directional actuation of plane structures of revolution. The PFC actuator is designed in the form of a thin annular disk where the continuous piezoelectric fibers are periodically distributed along the circumferential direction to yield the directional actuation along the radial direction in the cylindrical principal material coordinate system. This kind of microstructure of the annular PFC actuator yields its radially varying electromechanical properties that are determined through the asymptotic segmentation of its (PFC) volume into a large number of microvolumes of different fiber volume fractions. The closed-form expressions for the effective electromechanical coefficients of the microvolumes are derived, and the corresponding verification is carried out through the numerical homogenization using finite element procedure. The results reveal the indicative magnitude of an effective piezoelectric coefficient ( $$e_{31})$$ e 31 ) that quantifies the directional actuation along the radial direction. But, the magnitude of this coefficient ( $$e_{31})$$ e 31 ) decreases indicatively with the increasing radius, and thus the annular PFC actuator is redesigned in a special manner for the improved magnitude of the coefficient ( $$e_{31})$$ e 31 ) at any radius. With these improved properties of the annular PFC actuator, its indicative actuation capability in control of vibration of an annular plate is observed, and thus this annular PFC actuator may be recommended for active control of plane structures of revolution specifically where the actuation along the radial direction is the major requirement.