Effect of Ca on the Microstructure and Mechanical Properties in Mg Alloys

Rare Earth (RE)-free Mg alloys suffer from low formability due to strong textures and highly anisotropic deformation modes. In the present study, we examine the effects of Ca addition on microstructure and mechanical properties of Mg-Li-Ca and Mg-Zn-Ca alloys. Based on experimental observations, Ca is reported as the element that should solid-solution strengthen Mg-Li alloys due to its significant size mismatch and weaken the texture in Mg-Zn alloys, similarly to the RE contribution in Mg alloys. Using the density functional theory (DFT) we examine the intrinsic type II stacking faults in the basal and pyramidal I planes. We try different alloy compositions in order to understand the solid-solution effect on the different stacking faults and reduce the high plastic anisotropy in Mg alloys mechanical properties.