I wish to perform an analysis on a hyperelastic material in ABAQUS. Reading the manual I discovered that nominal (engineering) stress / strain data is required for defining a hyperelastic material model.
The experimental data I have is presented as Cauchy stress vs. stretch. From my understanding of mechanics Cauchy stress is True stress, is this correct?
Also, I was wondering if it is acceptable to convert Cauchy stress to nominal stress by rearranging the equation given in the plasticity section of the ABAQUS manual, ie:
s_true = s_nom * (1 + e_nom) where [s = stress, e = strain]
Any insight would be greatly appreciated!