Plastic modeling only by Abaqus built-in property settings

[robertt3]

In my project, the material shows high plasticity, about which I know little. After reading some related papers, I find that the key is to simulate the cyclic uniaxial tensile test data from experiments. I used the Combined Hardening and Cyclic Hardening in Plastic(Mechanical-Plasticity-Plastic). But it seems not accurate enough. I wander if there is a more feasible method to simulate the material behavior.

 

[SWComposites]

What is the material? Metal? Plastic?
What are the different color lines on the plot?
What does your model look like?
Where are you extracting stress and strain from the model?

 

[robertt3]

Sorry for missed information. The material is nylon wire. The different colors means tension cycle with increasing maximum strain. The model for material simulation is just a rod with one side fixed and one side moved with a prescribed displacement along the rod. The free end displacement and the fixed end reaction force were recorded(black curve in the figure).

 

[SWComposites]

So the grey lines are test data, and the black/red/blue lines are the model results?
I don’t think a “hardening” model is intended for plastics.
But I don’t have an Abaqus manual to go look up the different material models available.
If you have the material stress-strain curve data, you should be able to use that with a general nonlinear material.

 

[FEA way]

Check the "Best Material Model for Nylon (PA66)" blog article on PolymerFEM website. There they come to the conclusion that the best choice when it comes go Abaqus material models is PRF but it’s a really complex model. However, elastic-plastic with combined hardening also gives good results.

 

[robertt3]

Thanks FEA way, it really helps!

 

[robertt3]

Dear FEA way, have you ever used the PolyUMod? Do you know how to export UMAT of the desired material model. The "export model" button only offers parameters without UMAT.

 

[FEA way]

I've never used that software but its developer (Jorgen Bergstrom) is quite active on his website and even has a forum so maybe ask there.

 

[robertt3]

Thanks for your advice!