Dynamical and structural properties of metallic liquid and glass Zr48Cu36Ag8Al8 alloy studied by molecular dynamics simulation

Abstract

The structure and dynamics of the Zr48Cu36Ag8Al8 alloy were investigated by molecular dynamics simulation method using the embedded atom method (EAM) and tight-binding (TB) potentials. Total structure factors and pair distribution functions calculated from both potentials are in good agreement with the reported experimental data. The glass transition temperature was determined more easily by using the Wendt-Abraham parameter, which we modified with small changes. The fraction of 1551-bonded pairs and Zr-, Cu-, Ag- and Al-centered icosahedral-like clusters increased with decreasing temperature. High fractions of Cu-, Ag- and Al-centered perfect icosahedra and Zr-centered icosahedra-like clusters were detected in both supercooled liquids and glasses. The critical temperature was determined to be ~760.65 K from mode coupling theory. Although the results for the EAM and TB potentials were largely consistent with the experiment, aggregations were detected in the Ag and Al atoms at low temperatures for the EAM potential.