Editors: | F. Kongoli, E. Aifantis, R. Das, V.Eremeyev, N. Fantuzzi. |
Publisher: | Flogen Star OUTREACH |
Publication Year: | 2022 |
Pages: | 116 pages |
ISBN: | 978-1-989820-56-8(CD) |
ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
Recently the interest in flexoelectricity-related phenomena grows with respect to possible applications in MEMS and NEMS for energy harvesting, sensors and actuators. Flexoelectricity is the general property of dielectrics. Although the magnitude of the flexoelectric response is small, in general, its contribution may become dominant at the nanoscale. The static flexoelectric response relates the electric polarization with the strain gradients and vice versa whereas dynamic flexoelectric response includes time derivatives of the polarization in the kinetic energy. In addition, the surface/interfacial flexoelectricity is known [1, 2], which includes surface/interfacial densities of strain and kinetic energy.
We discuss the influence of dynamic flexoelectric properties and surface flexoelectricity on vibrations of nanometer-sized structures as nanobeams and nanoplates considering all mentioned above responses considering oscillations of a nanobeam. For simplicity, we consider isotropic materials and infinitesimal deformations. We apply the Timoshenko-Reissner-Mindlin-type kinematics. In other words, we consider a beam with kinematicallly independent translations and rotations. Various boundary conditions are considered. For the derivation of the governing equations we used the least action principle generalized for dynamic flexoelectricity. Here the least action functional includes both surface and bulk strain and kinetic energies.The eigen-frequencies are calculated and their dependence on the material parameters are analysed.