The Effects of the Addition of Ca, Gd, La, and Y on Mechanical Properties and Microstructure of Pure Magnesium

Abstract

The effects of different elements on the mechanical properties and microstructure of pure Mg were studied by XRD, SEM, and tensile tests. The results show that with the addition of 1wt% Ca, Gd, La, and Y elements alone, different second-phase particles appear in the microstructure of Mg-1X. The addition of Gd and Y elements generates a small amount of Mg5Gd and Mg24Y5 particles, respectively. In contrast, the addition of the Ca element generates a large number of coarse Mg2Ca particles, and the addition of the La element generates a large number of fine and evenly distributed Mg12La particles. After extrusion, the extruded Mg-1X magnesium alloy shows a fine equiaxed recrystallization structure. All four alloys show bimodal texture distribution with deflection along the ED direction, and the texture deflected along the TD direction appears in Mg-1La alloy. The tensile test shows that the yield strength of MG-1La alloy is the highest when it is drawn along the ED direction. The yield strength of Mg-1La alloy is the lowest when it is drawn along TD.