Effects of Y on Microstructure and Mechanical Properties of Extruded Mg-5Al-1Ca Magnesium Alloys

The influence of Y content on the microstructure and mechanical properties of the Mg-5Al-1Ca magnesium alloy in the extruded state was investigated. Characterization of the alloy's microstructure was conducted using x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron backscatter diffraction (EBSD) techniques. The results indicated that the mechanical properties of the extruded Mg-5Al-1Ca-xY alloy exhibit a trend of initial enhancement followed by a decline with increasing Y content. The optimal mechanical properties were achieved with a Y content of 1.5 wt.%, where the alloy exhibited a yield strength of 259.4 MPa, tensile strength of 295.6 MPa, elongation of 19.4%, and hardness of 81.6 HV. These values represent improvements of 30.7, 12.9, 41.4, and 11.7%, respectively, over the alloy without the addition of Y. Concurrently, the addition of Y was found to diminish the basal texture of the alloys and increase the basal Schmid factor, thereby facilitating slip and resulting in improved plasticity.