Bending of piezoelectric actuators

An analytical solution of total deformations and stresses due to piezoelectric deformations and to external force is given for piezoelectric bending actuators composed generally of n layers. The deflection w(L) of the free end and the blocking force P s are discussed in detail for actuators composed of two or three layers. Actuators made from piezoelectric ceramics show some deviations, i.e. hysteresis and non-linearity, from predicted linear dependence of w(L) on the applied voltage. These deviations are due to the voltage dependence of piezoelectric parameters in this material.