Defining Hyperelastic rubber with tensile properties using data

[LottedB]

I have got the following properties for a rubber,
How do I put this in abaqus if I want to define a hyperelastic rubber?

Tensile properties
Tensile strength at max [MPa] 20.6
Elongation at break [%] 345
Modulus 25% [MPa] 6.0
Modulus 50% [MPa] 6.9
Modulus 100% [MPa] 7.6
Modulus 200% [MPa] 11.9
Modulus 300% [MPa] 18.2

I also have planar shear properties and Compression stress-strain properties

 

[FEA way]

You have to choose hyperelastic material behavior (or use *HYPERELASTIC keyword) and select one of a several available models:

- ARRUDA-BOYCE - specify: μ, λ_m, D, T
- MARLOW - specify test data
- MOONEY-RIVLIN - specify: C_10, C_01, D_1, T
- NEO HOOKE - specify: C_10, D_1, T
- OGDEN - for default 1 order of strain energy potential (N=1) specify: μ_1, α_1, D_1, T
- POLYNOMIAL - for default 1 order of strain energy potential (N=1) specify: C_10, C_01, D_1, T
- REDUCED POLYNOMIAL - for default 1 order of strain energy potential (N=1) specify: C_10, D_1, T
- VAN DER WAALS - specify: μ, λ_m, α, β, D, T
- YEOH - C_10, C_20, C_30, D_1, D_2, D_3, T
- USER - only in Abaqus/Standard, used when hyperelasticity is defined in UHYPER subroutine

Most of these parameters are unnamed constants used to describe hyperelasticity models. To understand their meaning you will have to take a look at the equations in the "Hyperelastic behavior of rubberlike materials" chapter of the Materials Guide in Abaqus documentation.

For sure it may be hard to get such advanced parameters for your material but there's another option. You can specify test data for these models (uniaxial, biaxial, planar or volumetric). There you just have to specify nominal stress vs nominal strain pairs from physical test. Then add TEST DATA INPUT parameter to *HYPERELASTIC keyword and Abaqus will compute the aforementioned constants from the specified test data.