data for constitutive law of NBR-70?

[cloche]

Hi,
does anybody have "stress-strain" experimental data for Nitrilic Rubber NBR-70?
I need to calculate a Mooney-Rivlin constitutive law for this material to be included in a FEM analysis, and in order to do that in the most "exact" way I'd need:
- sigma-epsilon data (or true-stress / true-strain, it doesn't matter) for one single monotonic uniaxial test
- the same for a biaxial test (if possible)
- the same for an "hydrostatic compression" test.

If you redirect me to "femplastics" website, please tell me the exact link because I've already tried there and the data I got were completely unusable in the FEM I use (ANSYS).

Thanks in advance,

Claudio

 

[jorgenb]

Hi Claudio,

You can find experimental data and various model predictions for NBR on the following link.

Best of luck,
Jorgen

(polymerFEM.com)
Information about advanced FEM of polymers.

 

[cloche]

Hi Jorgen,

thank you for the advice. I already tried there and could find only uniaxial compression data for NBR-70. It's already a good start, but my application involves a non neglectable part of shear, so I still need to find data for this...

Bye!

Claudio

 

[RvL04]

Hi Claudio;

When you say shear, do you mean a pure shear (planar tension), a simple (uniaxial) shear, or a torsional shear? You could always consider getting your NBR tested directly (if only to double check that the values you're using in your model are realistic). A company that does shearing tests, as well as biaxial and hydrostatic compression, is Axel Products; they also seem to work together with ANSYS a lot, so their data should work very well in your model.

Ron