Non-linear finite element simulations allow to explore the behavior of structural elements in particular conditions where the approximations of the linear model are no longer totally valid.
In addition to the nonlinearities due to deformations, it is also possible to include nonlinear material behaviors in the simulations. In the example shown in the figure, the behavior of a spring subjected to an increasing load was studied. In some points this load exceeds the elastic limit of the material, so that only with a non-linear analysis it is possible to reconstruct the real displacement / stress curve of the element.