Modelling of plastic deformation in magnesium

In the present contribution, a viscoplastic rate-dependent constitutive model based on Schmid’s law has been used to designate the activity level of pure magnesium deformation systems. A crystal plasticity model in the framework of finite elements was used to investigate the deformation systems on the scale of single- and polycrystals. Twinning has been modelled by coupling between finite shear and subsequent lattice rotation. It is shown for pure magnesium, that twinning can affect the slip systems activities and therefore changes the hardening mode within the crystal as a result of crystal reorientation. Furthermore, the twinning evolution during in plane and through-thickness deformation of pure Mg polycrystal rolled plate reveals that tensile {10-12} and compression {10-11} twinning have different effects on the mechanical response.