Effect of Al addition on structure and dynamics of Zr-Cu-Al glass-forming alloy

Abstract

Classical molecular dynamics study of metallic glass-forming alloys, Zr36Cu64 and Zr47Cu46Al7, is carried out to acquire atomic level understanding of the microalloying effect of Al atoms on the structure and dynamics of the alloy. The results indicate that in comparison to hard sphere-like atomic packing in the binary alloy, microalloying of Al brings in a fundamental modification in the atomic packing due to soft sphere-like Cu-Al bonding due to chemical short-range ordering (CSRO). In the ternary alloy, CSRO is found to homogenize the topological packing of the icosahedra (<0,0,12,0 > ). Microalloying also impacts the single particle dynamics at the timescale of β-relaxation and could have important implications on the mechanical properties of the glasses prepared from this alloy.