Executive Summary : | Magnesium (Mg) alloys, as the lightest commercially available structural metallic materials, have gained significant research interest due to their high specific strength, stiffness, damping properties, and recyclability. However, their widespread applications are hindered by poor room temperature formability, high anisotropy, and complexity introduced by profuse twinning. This is due to the insufficient number of easily activated slip systems in their hexagonal close packed (HCP) low-symmetry crystals, which makes twinning a prominent mechanism to accommodate plastic deformation. The development of an experimentally informed discrete twinning crystal plasticity model is proposed to accurately represent mechanical twinning and its interaction with dislocation slip, predicting the micromechanical behavior of Mg alloys. The model will be implemented in the crystal plasticity module of the DAMASK simulation kit, with Monte-Carlo sampling adding stochasticity and determining the state of the material point (twinned or untwinned). The model will treat nucleation and growth as distinct events, and twinning of a material point is formulated in terms of a sudden jump in plastic deformation gradient (Fp). Post-validation, the model will be helpful in designing Mg alloys with desired properties, rectifying the shortcomings of existing modeling approaches. |