Dear Sankar,

The best way is to validate Experimental data.

Dear Sankar,

material calibrations are based on optimization procedures. For example for typical von mises plasticity with isotropic hardening the formula is stress = Stressyield + K plast_strain ^ n. The material parameters are the hardening modulus K and hardening exponent n. Starting with an initial guess a simple uniaxial loading model with one solid is solved and the stress strain curve is compared with the experimental data. Then with optimization methods a better prediction of the material parameters is calculated and the same problem is solved again until the calibration is successful.

the elastic plastic equations are governed by typical hardening curve...refer to any standard book on plasticity or check the link below:

https://abaqus-docs.mit.edu/2017/English/SIMACAEGSARefMap/simagsa-c-matdefining.htm#:~:text=Abaqus%2FCAE%20allows%20you%20to,further%20in%20Creating%20material%20calibrations.