Effect of Y on the structure-property relationship of Mg65Cu25Y10 metallic glass

Abstract The effect of Y minor addition on the structure-property relationship of Mg65Cu25Y10 metallic glass was investigated through molecular dynamics simulations. The average local five-fold symmetry is reduced and the number of quasi-nearest atoms increases in Mg65Cu25Y10, indicating a lower atomic packing. This fact is inconsistent to the normal effect of minor elements to enhance the glass-forming ability by enlarging the atomic packing of the systems. Although the reduce of atomic packing, the numbers of icosahedra and some other Kasper polyhedra with the fewest disclinations increase in Mg65Cu25Y10. That might be the reason for the larger glass forming ability of Mg65Cu25Y10 than Mg65Cu35. Moreover, the strength of Mg65Cu25Y10 is not weakened by the low atomic packing, which might result from the strong chemical bonding of Cu-Y. Our results are helpful to understand the effect of minor elements on the properties of metallic glasses.