Texture Evolution of a Fine-Grained Mg Alloy at Dynamic Strain Rates

AMX602 (Mg-6% Al-0.5% Mn-2% Ca) is a high strength Mg alloy that was manufactured by the spinning water atomization process (SWAP) and extruded into a plate geometry. The processing produces an alloy with a weak rolling texture (for Mg) and grains between 0.5 and 5 mu m. Quasi-static and dynamic compression experiments were carried out to probe the material's mechanical behavior in the three processing directions. The tested plate showed deformation mechanism induced anisotropy consistent with what has been observed for other Mg alloys. The texture evolution was measured after loading in the three directions using X-ray diffraction at the Cornell High Energy Synchrotron Source (CHESS). A computationally efficient crystal plasticity model that demarcates twinning, basal slip, and non-basal slip mechanisms was utilized to predict the texture evolution and compared to the experimental texture. The model was able to predict the reorientation of grains associated with twin dominated yielding in the extrusion and transverse directions, and strengthening of the texture associated with slip dominated deformation in the normal direction.