Validating a polycrystal model for the elastoplastic response of magnesium alloy AZ31 using in situ neutron diffraction

In situ neutron diffraction is used to assess the development of internal elastic strains within the grains of magnesium alloy AZ31 processed via conventional extrusion and equal channel angular extrusion. An elastoplastic self-consistent polycrystal model is used to simulate the macroscopic flow curves and internal strain developments within the distinctly textured magnesium alloy samples. The parameters of the model are the critical resolved shear strengths and hardening behaviors of the dislocation slip and twinning mechanisms which operate within this hexagonal close-packed alloy. The results indicate that a single constitutive model can predict the behavior if it explicitly accounts for the effects of crystallographic texture and grain size. The polycrystal model presently accounts for grain size in an ad hoc manner. (c) 2006 Acta Matcrialia Inc. Published by Elsevier Ltd. All rights reserved.