Abstract
"Ferroelectrics/ferroelastics" means a class of the material nonlinearity of electro-mechanical coupling problem, and it involves "domain switching" phenomena in each crystalline scale of ceramics. To solve such a kind of problem, conventional FEM for the electro-mechanical coupling problem would not be appropriate and hence, an alternative FEM, which will be proposed here, would be required. This is because the nonlinearity is mainly interpreted as the loss of material stability, which is usually described by using incomplete thermodynamic functions. To utilize the incomplete thermodynamic functions, finite element discretization should be consistent with them. It means that independent variable about electrics for the discretization should be vector potential ψ instead of scalar potential φ, which is called "electric voltage" and is used in the conventional FEM.
