| Popis: |
Flexoelectricity is a different electromechanical coupling without this material symmetry limitations, hence universal for all dielectrics. Flexoelectricity relies on symmetry breaking beyond the material chemistry by either boundary conditions (bending, torsion), topology (architected metamaterials), the combination of multiple materials (composites) or surface effects (surface relaxation, surface instabilities in soft materials). In the present work, we explore a different symmetry-breaking mechanism, namely graded material properties. As in functionally graded materials, the sought-after property is the symmetry-breaking gradient itself. Apropos this goal, we extend the continuum mathematical and computational model for flexoelectricity and its implementation developed in the research group to account for continuously varying mechanical and electrical properties. The research made aims at finding an additional alternative to lead-based piezoceramics used nowadays. The studied linearly varying gradations show promising results with effective piezoelectric properties laying only an order of magnitude below the best piezoelectrics such as PZT and BaTiOFlexoelectricity is a different electromechanical coupling without this material symmetry limitations, hence universal for all dielectrics. Flexoelectricity relies on symmetry breaking beyond the material chemistry by either boundary conditions (bending, torsion), topology (architected metamaterials), the combination of multiple materials (composites) or surface effects (surface relaxation, surface instabilities in soft materials). In the present work, we explore a different symmetry-breaking mechanism, namely graded material properties. As in functionally graded materials, the sought-after property is the symmetry-breaking gradient itself. Apropos this goal, we extend the continuum mathematical and computational model for flexoelectricity and its implementation developed in the research group to account for continuously varying mechanical and electrical properties. The research made aims at finding an additional alternative to lead-based piezoceramics used nowadays. The studied linearly varying gradations show promising results with effective piezoelectric properties laying only an order of magnitude below the best piezoelectrics such as PZT and BaTiO. |
