Fabrication and high durability of functionally graded piezoelectric bendingactuators

Abstract

A new type of functionally graded (FG) piezoelectric bending actuator wasproposed by the present authors in their former study and the advantage of thenew actuator over the traditional bimorph and unimorph actuators in internalstress distribution was illustrated by simulation results. In this study, thefabrication process of FG piezoelectric bending actuators is developed and thecharacteristics of the fabricated actuators are investigated. The materialcompositions with different dielectric and piezoelectric constants were selectedfrom the Pb(Ni1/3Nb2/3)O3–PbZrO3–PbTiO3 family and used as the four layersin the new FG piezoelectric actuator. The piezoelectric constant and dielectricconstant were graded oppositely in the thickness direction. The durability of thefabricated FG piezoelectric actuators was measured in a vibration test andcompared with that of the traditional bimorph actuator to evaluate theimprovement of performance. The results show that the durability of the FGpiezoelectric actuators is much higher than that of the bimorph actuator.