梯度压电梁的挠曲电和表面效应

In this paper, a piezoelectric beam model with flexoelectricity and surface effects is proposed. An energy variational principle is postulated to develop the governing equations and boundary conditions. Moreover, the strain gradient coefficient and flexoelectric paprameter are introduced to account for higher order coupling effects of underlying microstructure. Then the bending problem of a cantilever beam is solved to illustrate the theory. It is found that the deflection of the cantilever may depend strongly on the so-introduced gradient-related effects and surface properties. Flexoelectricity can soften the beam stiffness, while strain gradient may enhance the beam striness. And also, the electric field distributions obtained by the models with and without the coupling of strian gradient have a great difference.