The poling design of a shear mode piezoelectric actuator

Abstract

A shear mode PZT actuator for the microdroplet ejecting system is proposed. The plate-shaped actuator poled with remnant polarization perpendicular to the actuating field induces a piezoelectric shear effect. Two poling designs for the shear mode piezoelectric actuator are compared by both analysis and experiment. The two poling designs are the single-surface poling design and the dual-surface poling design. The single-surface poling design arranges the poling electrodes on only one surface, while the dual-surface poling design arranges the poling electrodes on opposite surfaces. Although the single-surface poling design is convenient for the poling process, its requirement for a higher poling voltage to achieve a coercive field induces specimen failure by surface cracking. So, the dual-surface poling design is preferred because a higher yield and better electromechanical coupling characteristic can be obtained. In both the poling designs, the relation of the shear piezoelectric coefficient, d15, and the actuating electric field are obtained with three kinds of sample thickness.