Some nonlinear effects observed in rubbers, such as hysteresis in stress-stretch curves, residual strains, and stress softening effects, are not accounted in the formulation of common hyperelastic materials. See Mullins Effect in the Structural Mechanics Theory chapter.

Use the Mullins effect subnode to define the properties for modeling the stress-softening phenomenon under cyclic loading. The Mullins effect can be used together with Layered Hyperelastic Material.

See the documentation for the Mullins Effect node in the Layered Shell chapter.

The Damage function defines the model for Mullins effect. Select Ogden-Roxburgh or Miehe.

For Ogden-Roxburgh enter the following settings:

For Miehe enter the following settings:

Damage saturation Wsat. The default is 1 MJ/m3.

Physics tab with Layered Hyperelastic Material node selected in the model tree: