Structure and transport properties of the liquid Al80Cu20 alloy – A molecular dynamics study

Abstract

Structural and transport properties of the liquid Al80Cu20 alloy have been investigated performing molecular dynamics simulations using a new parametrization of modified embedded atom model (MEAM) potential method retained to the available ab initio molecular dynamics (AIMD) and experimental data. Local atomic structural changes, including chemistry and topology, have been studied and discussed with the literature data. Strong chemical bonding of unlike atoms in comparison to like-ones is found and confirmed by the available literature data. High degree of topological complexity and icosahedron-like type atomic clusters of increasing abundance with temperature decrease are observed, and their influence on short-range chemical ordering as well as transport properties have been defined. Almost perfect agreement between experimental data and the presented MEAM-MD simulations has been registered for the self-diffusion coefficient of Cu atoms in comparison to significant underestimation of experimentally determined inter-diffusion coefficient of the liquid Al80Cu20 alloy. Viscosities simulated, using two MD-based methods, exhibit a slight overestimation of experimental data.