Experimental strain-hardening behaviors and associated computational models with anisotropic sheet metals

Several anisotropic hardening models with simple loading conditions are proposed, including exponential hardening model, linear hardening model and multi-linear hardening model (which also suits for using the experimental data directly). Three special hardening curves, in the 0°, 45° and 90° angles, respectively, measured against the rolling direction, are the special cases of the proposed hardening models. These models make sense to be applied for simulating forming processes of the planar anisotropic hardening sheet metals, in particular for determining the springback and FLD of formed parts. In order to describe this view further, the constitutive relations of stress and strain, based on the plastic potential flow rule with isotropic hardening and kinematic hardening assumptions, have been discussed briefly. And then, the corresponding results of constitutive relations dependent on the proposed hardening models of materials will be represented, respectively.