(V)umat

I will be developing constitutive material models into commercial FE codes for nonlinear elasticity and searching for good books to get started for computational aspects. There are many good books for computational plasticity but I did not find any for nonlinear elasticity. Suggestion for good books or references is welcome.

Hello all, 

I am a beginner in UMAT implementation. I want to implement a Umat soubroutine for a kinematic hardening model using Hill's yield criterion. However, after looking in different courses and books, I remarked that the jacobian matrix derivation steps from the constitutive equations are not explicitaly defined.

Can anyone help me to understand this derivation step so that I can apply it for the Hill's criterion ?

Thank you in advance,

Regards,
Haithem  

As we know, Abaqus/(v)umat provides the temperatures at each material point at the end of the increment, but in a thermo-mechanical problem, the heat induced by plastic deformation is unknown before the plastic strain is calculated. So, How the temperatures at material points in abaqus are updated?

Thanks in advance.

Y. T.