Synthesis of Sm–Al metallic glasses designed by molecular dynamics simulations

Solidification of the Sm-rich Al–Sm alloys has been studied using a newly developed Al–Sm embedded atom model potential by molecular dynamics (MD) simulations. We use descriptors for glass forming ability that have been previously validated for Al-rich Al–Sm alloys, and we predict that among the Sm-rich alloys the best glass formers have compositions between 65 and 75 at.% of Sm. To test this prediction, Al₃₅Sm₆₅ and Al₂₅Sm₇₅ alloys were synthesized by melt spinning. These alloys have been found to be good glass formers, in agreement with predictions from MD simulations. We also synthesized Al₁₀Sm₉₀, which according to MD results should have a low glass forming ability. Indeed, after the melt spinning, the Al₁₀Sm₉₀ was found to be crystalline as verified by multiple experimental characterization techniques. This is the first time that Sm-rich Al–Sm metallic glasses with enhanced glass forming ability have been experimentally synthesized. Our results also demonstrate the capability of specific structural descriptors to predict glass forming ability of Al-based alloys.