Uniaxial Testdata imput for Abaqus (Norms and calculations)

[frankyman]

I have a problem to understand my Abaqus (6.8). I can use test data (uni- biaxial or planar stress/strain) to calculate the coefficient for Mooney-Rivlin ore one of the other. But which norm Abaqus like. (ISO 37, ASTM D412, ISO527 ….) I can’t found any information about this. Because the results can have large aberration.
The other is. Can I use this reality (true) data or must I convert it to nominal strain/stress?
My problem ist a rubber of TPA and my focus is directed of the reaction forces in my fem-model. The model work with 30 – 40% elastic strain.
Can everybody give me a tip.

[Jorgen]

It does not matter what standard you use for the experimental testing. All you need is experimentally determined stress and strain data, for one or more loading modes.

Yes, if you want to use the built-in Abaqus feature for determining the material parameters then you need to convert the experimental data to engineering strain and engineering stress.

-Jorgen

[frankyman]

Ok, now I have seen that my polymer is tested with comparing norms and the results are nearly identical. If I use this data (ISO 37) the results are nominal or not? Because e_nom=l-l_0/l_0 and this is also written in the norm iso 37. And abaqus like nominal test data.

[Jorgen]

I don't recall the details of ISO 37, but it sounds like nominal to me.