Modified Schmid factor analysis and calculation of magnesium crystals under three-dimensional stress states

This study proposed a modified Schmid factor (m-SF) to strictly calculate the theoretical SF values of a crystal magnesium (Mg) under complex stress. Systematic calculations and investigations were conducted to determine the impact of the three-dimensional stress state and its components on the SF values of basal <a>, prismatic <a>, pyramid <a>/<c+a> slips, as well as compression/tension twins. The results indicated that the effect of shear stress on SF was smaller than normal stress, and different deformation mechanisms had varying levels of sensitivity to the a/c-axial stress components, which was due to the decomposition validity of the stress components on the slip/twinning system. Additionally, some typical mechanical characteristics and deformation behaviors of Mg alloys are adequately interpreted by these results.