An Overview

Abstract

Piezoelectric materials have found widespread use as sensors and actuators and are used in many areas such as microelectromechanical systems (MEMS), control systems, navigation, medical, and aerospace industries. When the electric field is applied in parallel and perpendicular to the direction of initial polarization, it induces the vibrations of the piezoceramic due to $d_{31}$ or $d_{33}$ and $d_{15}$ effect, respectively. Here, $d_{31}$ or $d_{33}$ and $d_{15}$ are the piezoelectric coefficients. In piezoelectric actuators, the shear effect has been found appealing for engineering applications since piezoelectric coupling coefficient for shear $d_{15}$ is much higher than the other piezoelectric coupling coefficients; lateral $d_{33}$ and longitudinal $d_{31}$ coefficients. The shear actuators can be used to induce and control the flexural vibrations of beams and plates. Hence, actuators based on shear effect are an attractive choice as compared to the actuators which are based on other effects.