Evolution of the 3D plastic anisotropy of HCP metals: Experiments and modeling
Résumé
A two-surface, pressure-insensitive plasticity model is further developed to represent the mechanical response of hexagonal close packed metals. The model describes the 3D plastic anisotropy of a material, the tension–compression asymmetry, and the consistent evolution upon straining of both the net anisotropy and the asymmetry. The model may be viewed as a reduced order quasi-crystal plasticity model whereby the two activation surfaces represent glide- and twinning-dominated flow. The two-surface formulation enables to represent independent, yet coupled, hardening laws in terms of effective plastic strains accumulated on either generic deformation system. Application of the model to a discriminating data set assembled for a magnesium alloy thick plate illustrates the capabilities and versatility of the modeling approach.