Large strain behaviour of very thin aluminium sheets under planar simple shear

The finite element method is used to numerically simulate the large strain behaviour of thin rolled aluminium alloy sheets under planar simple shear. The numerical analyses are performed on both macroscopic and 'mesoscopic' levels. In the macroscopic calculation, each material point is represented by an aggregate of single crystals, and the Taylor-type polycrystal plasticity model gives the constitutive response at an integration point. In the mesoscopic study, a material point or a polycrystal is represented by an 'unit-cell' in which an element of the finite element mesh represents a single crystal, and the constitutive response at an integration point is given by the single crystal constitutive model. Numerical results are compared with experimental data found in the literature. The differences in predicted numerical results between the macroscopic and mesoscopic approaches are discussed.