Electronic work function, surface energy and electronic properties of binary Mg-Y and Mg- Al alloys: A DFT study

The first principles are carried out to investigate the electronic work function, surface energy and electronic properties based on the new compositions evaluated previously for binary Mg-Al alloys and Mg-Y alloys. The calculated results imply that Mg15Al and MgY could be good corrosion resistant materials due to the work function close to or less than that of magnesium matrix. Meanwhile, the work function and surface energy of Mg15Al show the opposite trend with different end surfaces, which is different from the Mg3Al, MgAl and similar to the Mg monomer reported previously. It may be attributed to the properties of Mg15Al with lower aluminum content close to those of a monomer rather than an alloying compound. Compared with Mg-Al alloys, the corrosion resistance of Mg-Y alloys tends to increase with the increasing of Y content. Our results provide considerable insight into the stabilities of Mg-Al alloys and Mg-Y alloys surface, provide the data of the corrosion resistance design of magnesium alloys.