Abaqus HYPERFOAM Material Model Parameters

[mahoni]

Hi everybody.
The Abaqus Hyperfoam material model is based on material parameters.
Abaqus defines the parameters automatic. The Foam is characterized by a combination of uniaxial tension, uniaxial compression and simple shear experiments. I am trying to define the parameters by hand to get a better approach betwenn experimental data und calculated results.
I look for a physically background of the parameters. Can anybody help me to describe the parameter alpha. What physically interrelation exists?
Thanks for help.
mahoni

[Jorgen]

The hyperfoam model is a phenomenological model and as such does not have a direct relationship with the physics of the deformation mechamisms. It is possible, however, to correlate the material parameters to the predicted stress-strain curves. The following is a brief summary:
:arrow: mu is the shear modulus (ie stiffness)
:arrow: alpha specifies the shape of the stress strain curve (ie large strain behavior)
:arrow: beta specifies the shape of the volumetric response

These comments are not mathematically precise, I suggest that you do trial-and-error, or a more automatic optimization to find the material parameters for the materials that you are interested in.

Best of luck,
Jorgen