Finite Element Model of Flexoelectric Responce with Micro Scale Effect Based on a Modified Couple Stress Theory

Compared with piezoelectricity, flexoelectric effect has a significant size sensitivity because the proportional relationship between external flexoelectric polarization and internal strain gradient. Usually in micro scale or nano scale, flexoelectric effect in dielectric solids can magnify better electromechanical couple performance than piezoelectric effect. At present, plentiful research focuses on the theoretical modelling of the flexoelectric materials and its micro or nano structures. However, the research on numerical modeling of flexoelectric responce with micro scale effect is much fewer. Therefore, the finite element modelling of flexoelectric response in micro scale is of great meaning and necessary. In this study, a finite element model of flexoelectric responce with micro scale effect based on a modified couple stress theory is proposed. And a cantilever beam of flexoelectric materials in micro scale is investigated for validation.