Hyperelastic Stress Strain Curve

[stevenaking]

I am workin gwith a hyperelastic material. I have stress strain data from the supplier.

I have been trying to use the curve fitting tools for the Mooney-Rivlin model. When I go through the curve fir procedure, the resulting curve does not match the input data well at all. (see attached picture)

So, my first question is: Some FEA software will accept the ss data without doing a curve fit, just interpolating between data points. Is this an option for hyperelastics in Autodesk?

Second: Where can I find precise definitions of Simple Tension, Equibiaxial, P\ure-Shear, and Volumetric? I want to be sure I am putting my data in the right place. The help page on the curve fitting does not define these.

Thanks,

Steve

[Andrew.Sartorelli]

Hi Steve,

I'd recommend increasing the curve fit order from 2 to 5 or 7, that should allow for a better fit.