Entering Material Model for a Polymer using Multilinear hardening model
I am trying to use the plastic strain failure model for a material with the below stress-strain curve.
I use the relation introduced in this thread (https://studentcommunity.ansys.com/thread/multilinear-kinematic-plasticity-material-model-create-from-a-stress-strain-graph/) to obtain true stress-true strain curve and "plastic strain". But the problem is that large value of strain in this polymeric material leads to a negative value for plastic strain. The below table:
I wonder how I can enter this data for my material model in a multilinear hardening? And if I use Plastic Strain Failure criteria for failure, what value I should set for maximum EPS?
(I have attached the excel datasheet to this thread).