The Electrostriction multiphysics node (
) passes the electric polarization contribution to strain from the
Electrostatics interface to the
Solid Mechanics interface. In contrast to linear piezoelectricity, the electrostrictive strain is quadratic in polarization.
It also passes the mechanical stress contribution to polarization from the Solid Mechanics interface to the
Electrostatics interface, which is called the inverse electrostrictive effect.
The Label is the multiphysics coupling feature name. The default
Label (for the first multiphysics coupling feature in the model) is
Electrostriction 1.
The Name is used primarily as a scope prefix for variables defined by the coupling node. Refer to such variables in expressions using the pattern
<name>.<variable_name>. In order to distinguish between variables belonging to different coupling nodes or physics interfaces, the
name string must be unique. Only letters, numbers, and underscores (_) are permitted in the
Name field. The first character must be a letter.
The default Name (for the first multiphysics coupling feature in the model) is
efe1.
You can also select None from either list to uncouple the Electrostriction node from a physics interface. If the physics interface is removed from the
Model Builder, for example
Solid Mechanics is deleted, then the list defaults to
None as there is nothing to couple to.
In Electrostatics interface, the following two domains are applicable:
In the Solid Mechanics interface, the following domain material features are applicable:
When the Electrostrictive strain tensor is set to
Quadratic, one of the following options can be selected from the
Material symmetry list:
For the Anisotropic choice, a component of a 6-by-6 symmetric electrostrictive coupling matrix can be entered using either the
Voigt (default) or the
Standard option for the
Material data ordering.
For the Cubic crystal choice, only three independent components of the electrostrictive coupling matrix need to be entered.
For the Isotropic choice, you can enter two independent components of the electrostrictive coupling matrix using either Q-matrix (default) or M-matrix notations. Alternatively, you can enter values for the
Electrostrictive constant a1 and
Electrostrictive constant a2 (SI units: F/m) using the definitions according to either
Ref. 1 or
Ref. 2.
You can neglect the terms quadratic in the reversible polarization components in the expression for the electrostrictive strain by checking the check box Small reversible polarization. This functionality is applicable only when this coupling node is used as a part of either Ferroelectroelasticity or Electrostriction multiphysics interface, and the corresponding
Electrostatics interface is configured for hysteresis modeling.
When the Electrostrictive strain tensor is set to
Quadratic, deviatoric, the material is assumed to be isotropic, and you can enter the saturation electrostriction and polarization.