Temperature dependence of the solid-liquid interface free energy of Ni and Al from molecular dynamics simulation of nucleation

TL;DR

This study uses molecular dynamics simulations to analyze how the solid-liquid interfacial free energy of Ni and Al varies with temperature, providing insights into nucleation processes near melting points.

Contribution

It introduces a persistent-embryo method to accurately compute temperature-dependent interfacial free energy for Ni and Al, aligning with previous methods and extending understanding of nucleation.

Findings

Interfacial free energy {b3} varies linearly with temperature.

Extrapolated {b3} values agree with capillary fluctuation method data.

Nucleation free energy barriers estimated match brute-force MD results.

Abstract

The temperature dependence of the solid-liquid interfacial free energy, {\gamma}, is investigated for Al and Ni at the undercooled temperature regime based on a recently developed persistent-embryo method. The atomistic description of the nucleus shape is obtained from molecular dynamics simulations. The computed {\gamma} shows a linear dependence on the temperature. The values of {\gamma} extrapolated to the melting temperature agree well with previous data obtained by the capillary fluctuation method. Using the temperature dependence of {\gamma}, we estimate the nucleation free energy barrier in a wide temperature range from the classical nucleation theory. The obtained data agree very well with the results from the brute-force molecular dynamics simulations.