Modeling viscous behavior of material

[simulation_engineer_2022]

Hi everyone!

I wonder how one could implement specific relaxation material model to simulate stress change over time in Abaqus. The model itself looks like follows:

stress(t)=C1 * strain * time^C2 * exp(-C3/T)

C1, C2, C3 are known constants. I guess writing CREEP subroutine could help, but maybe it could be approximated by some built-in models? I would appreciate any advice on CREEP and built-in models.

Thanks in advance!

 

[FEA way]

The built-in creep models are described (with equations) in the documentation chapter Materials —> Inelastic Mechanical Properties —> Metal plasticity —> Rate-dependent plasticity: creep and swelling. If you need something formulated differently than those models, you will need a CREEP subroutine.