I am working on crystal plasticity anaisotropic UMAT model for finding plastic strain distribution in the different grains of super duplex stainless steel (1.4410).

I need to include Usermaterial constants in the material section of the ABAQUS model and i m unaware and have no idea how to get these parameters mentioned

strain rate sensitivity exponent  ----  N

Reference strain Rate               ---- a dot

initial resolved shear stress       ---- tau0

Critical resolved shear stress    ----- taus

These all parameters are used in Power law formulations (the formulation is attached to this question)

In that formulation halpha alpha is the hardening const of particular slip system

Please help me out in sharing some knowledge on these parameters and in finding out them.

Thanks in advance

Best Regards

Ravva Gaurav