Flexoelectric Effect on Bending Response of Functionally Graded Piezoelectric Sensors

摘要

Due to the remarkable flexoelectric effect of nano structures, the electro-mechanical coupling of nano piezoelectric sensors has been studied. This paper studies polarization distribution and induced voltage (or output voltage) of the functionally graded piezoelectric cantilever nanobeam by the generalized variational principle and linear piezoelectric theory. The equilibrium equation and corresponding general boundary condition of functionally graded sensors are obtained. Based on the graded model, the analytic forms of the deformation and output voltage are given. The numerical result reveals gradient parameters and flexoelectric coefficient have the significant influence on the output voltage and electric polarization for the functionally graded sensor. The strong piezoelectric gradient in sensors would cause the significant effective flexoelectricity, which could generate the large output voltage at the large structural size.