Helloo all....
I have written UMAT for glass fiber composites. [U]It works fine till failure then it fails to converge:(.[/U]
I understand problem lies in non linear tangent stiffness. I am supplying calculated stiffness matrix to DDSDDE.
[B]Can any one help or suggest most accurate coding of DDSDDE for my problem..????[/B]
Thanx in advance...
Im not quite sure I understand your question. If your DDSDDE matrix is not accurate enough, then can you not simply derive a more accurate version?
-Jorgen
I dont know what should I supply to DDSDDE.
I coded USDFLD instead of UMAT. I am having good agreement with experimental results.
I want to know that does ABAQUS have inbuilt non linear model for isotropic material..????
It can be quite challenging to derive an accurate DDSDDE (Jacobian).
I have derived & implemented a library of non-linear material models that can help accurately predict polymer behaviors (PolyUMod).
-Jorgen