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During the solidification of Al-Sm metallic glasses the evolution of the supercooled liquid atomic structure has been identified with an increasing population of icosahedral-like clusters with increasing Sm concentration. These clusters exhibit slower kinetics compared to the remaining clusters in the liquid leading to enhanced amorphous phase stability and glass forming ability (GFA). Maximum icosahedral-ordering and atomic packing density have been found for the Al 90 Sm 10 and Al 85 Sm 15 alloys, respectively, whereas minimum cohesive energy has been found for the Al 93 Sm 7 which is consistent with the range of compositions (from Al 92 Sm 8 to Al 84 Sm 16 ) found experimentally with high GFA.Keywords: metallic glass; short-range order; molecular dynamics; solidification.Metallic glasses (MGs) are known to have attractive mechanical properties such as high strength and high elastic limit, good corrosion and wear resistance and good biocompatibility [1,2,3]. However, the low glass forming ability (GFA) of some MGs has so far hindered synthesis of large MG specimens such as Al-base systems and therefore limited engineering applications of these materials. Many efforts have been devoted towards developing alloys with high GFA [1,4,5]. In particular, a number of studies focused on understanding of the MGs atomic structure and its relation to the MGs' mechanical properties

We carried out molecular dynamics simulations (MD) using realistic empirical potentials for the vapor deposition (VD) of CuZrAl glasses. VD glasses have higher densities and lower potential and inherent structure energies than the melt-quenched glasses for the same alloys. The optimal substrate temperature for the deposition process is 0.625×T g . In VD metallic glasses (MGs), the total number of icosahedral like clusters is higher than in the melt-quenched MGs. Surprisingly, the VD glasses have a lower degree of chemical mixing than the melt-quenched glasses. The reason for it is that the melt-quenched MGs can be viewed as frozen liquids, which means that their chemical order is the same as in the liquid state. In contrast, during the formation of the VD MGs, the absence of the liquid state results in the creation of a different chemical order with more Zr-Zr homonuclear bonds compared with the melt-quenched MGs. In order to obtain MGs from melt-quench technique with similarly low energies as in the VD process, the cooling rate during quenching would have to be many orders of magnitude lower than currently accessible to MD simulations. The method proposed in this manuscript is a more efficient way to create MGs by using MD simulations.

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