Variation of glass transition temperature of Al90Sm10 metallic glass under pressurized cooling

Abstract

In this paper, the role of hydrostatic pressure in Al90Sm10 bimetallic glass formation has been studied using molecular dynamics simulations with Embedded Atom Method (EAM) potential. The bimetallic glass is prepared by subjecting the Al90Sm10 alloy to hydrostatic pressure (P = 0, 2, 4, 6, 8 GPa) during cooling the melt (cooling rate~1 K/ps) and the variation in glass transition temperature is determined. It is observed that the glass transition temperature rises as applied hydrostatic pressure increases.RDF analysis indicates the enhancement in local ordering of the Al90Sm10 alloy with increasing applied pressure. Voronoi analysis of the bimetallic glass reveal that the glass-transition temperature behavior seems to be greatly influenced by distorted ICO-like structures Z14 < 0, 2, 8, 4>, Z13 < 0, 1, 10, 2>, Z13 < 0, 2, 8, 3>. However, population of T6 motifs (3661 motifs) remains constant irrespective of the variation in applied hydrostatic pressure. This work as a whole provides an insight towards co-relation between glass transition process and applied pressure during cooling along with underlying physics for Al90Sm10 bimetallic glass.