Maximum stress is roughly 111 MPa. When I solve the model (nonlinear analysis, nnlin geom ON), I get maximum stress values (both Von Mises and principal maximum) higer then the highest value in the stress-strain curve (this affect a wide part of the model, it isn’t just a few elements). This sound strange to me, expecially because the material has a perfect plastic behaviour from a certain strain. Here the two images of the model: Principal stress
@synt thank you for your advice: as you suggested I adopted a finer mesh in the area of interest, going from an average el. size of 0.5mm down to 0.1mm: results didn’t change, I still have values around 140MPa instead of the maximum value in the curve, 111 MPa.
Moreover, I tried with another material (same model, same loads, just different material) less ductile than the first I used, again adoptin gelasto-plastic behaviour such as this:
Young’s modulus is roughly 3 times higher than the initial material.
@FEAnalyst I see your point and I would agree if for one reason: maximum stress in stress-strain curve is lower than the value I should find in any of the integration points. Interpolating integration points to the nodes, should give me at least not accurate stress, but I don’t expect this huge difference (110 vs 140MPa in wide areas of the model is roughly 25% of difference!!!)
It’s because temperature is plotted in the same graph so there are different quantities on the Y axis. But temperature can be ignored here so it’s just yield stress - plastic strain plot of the input data for *PLASTIC.