Influence of Zr addition on the morphology of primary MgZn2 in the solidification microstructure of Zn-6Al-3Mg alloy

This study investigates the influence of trace zirconium on morphology of primary MgZn2 in solidification microstructure of Zn-6Al-3Mg alloy using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), electron backscatter diffraction (EBSD) and X-ray diffractometer (XRD). The results demonstrate that MgZn2 exhibits a single crystal structure. The erosion of the liquid phase on MgZn2 contributes to the formation of a secondary Al/MgZn2 structure. Furthermore, the increase of zirconium content accelerates the erosion of MgZn2. When the zirconium content is at 0.09 wt.%, the secondary Al/MgZn2 structure reaches its stability limit. These findings open up new perspectives for further research on Zn-Al-Mg alloys.