Study of viscosity of aluminum melt during glass transition by molecular dynamics and Green-Kubo formula

Abstract

Molecular dynamics study of shear viscosity behavior of liquid aluminum is performed. The embedded atom method potential is used at the simulation of isobaric cooling. The viscosity is calculated using the Green-Kubo formula. The stress autocorrelation functions are obtained in the range 300-1200 K. The calculated kinematic viscosity is in agreement with the experimental data for the temperatures above melting temperature. The steep change of the shear viscosity is found below 650 K which we associate with the glass transition and is in a good agreement with the temperature which is obtained using the calorimetric criterion Kolotova et al (2015 J. Non-Cryst. Solids 429 98). The viscosity coefficient can not be calculated using the direct atomistic simulations below that temperature.