Modeling the Effect of Alloying Elements in Magnesium on Deformation Twin Characteristics

摘要

HCP magnesium metals are widely used in different industries due to their low density and high specific strength. Their applicability is restricted due to poor formability and high anisotropy in deformation behavior. The formability of magnesium can be improved by alloying additions and this modification can affect macroscopic plastic anisotropy. Alloying additions can also significantly control the twinning process. In this work we use a crystal plasticity based Fast Fourier Transform model to characterize deformation twinning in different alloy types. In the model, the influence of alloying additions is represented through their effect on the critical resolved shear stress (CRSS) values for all slip and twinning modes. From this study, we build an understanding of the influence of alloying elements on twin growth and twin transmission behavior. A new plastic anisotropy measure is proposed to quantify the effects of alloying elements on some important twinning characteristics in magnesium alloys.