UMAT question

[prpasquali]

Hi all
I’m implementing a non-linear elastic constitutive law through UMAT subroutine. I get good results compared to analytical solutions of several problems only when I use very small time increments in the Step module. The question is if this procedure is just incremental or it’s also iterative? If not, is it possible to develop an iterative algorithm to obtain stresses as function of strains wih UMAT, independent of the time step utilized?
Thanks for the attention,
Paulo

[Jorgen]

I am not quite sure I understand your question. You should be able to take large time increments if you use an accurate Jacobian. Often a not so good Jacobian can lead to small time increments.

- Jorgen