Molecular dynamics study of melting of a bcc metal-vanadium II : thermodynamic melting

TL;DR

This study uses molecular dynamics simulations to analyze the melting process of vanadium, a bcc metal, focusing on surface premelting phenomena and their relation to surface atomic density.

Contribution

It provides detailed insights into the surface-specific premelting behavior of vanadium and establishes a correlation with surface atomic density, which was not previously characterized.

Findings

V(111) surface disorders first with increasing temperature

Disorder spreads into the bulk forming a quasiliquid film

Premelting hierarchy is inversely related to surface atomic density

Abstract

We present molecular dynamics simulations of the thermodynamic melting transition of a bcc metal, vanadium using the Finnis-Sinclair potential. We studied the structural, transport and energetic properties of slabs made of 27 atomic layers with a free surface. We investigated premelting phenomena at the low-index surfaces of vanadium; V(111), V(001), and V(011), finding that as the temperature increases, the V(111) surface disorders first, then the V(100) surface, while the V(110) surface remains stable up to the melting temperature. Also, as the temperature increases, the disorder spreads from the surface layer into the bulk, establishing a thin quasiliquid film in the surface region. We conclude that the hierarchy of premelting phenomena is inversely proportional to the surface atomic density, being most pronounced for the V(111) surface which has the lowest surface density.