Atomistic modeling of crystal-melt interface mobility of fcc (Al, Cu) and bcc (Fe) metals in STRONG superheating/undercooling states

Abstract

A detailed study of the mobility and kinetic properties of solid-liquid interfaces (SLI) with different types of crystal lattices (fcc-Al, Cu) and (bcc-Fe) metals in a wide range of temperatures and pressures was carried out using atomistic modeling. The ranges of maximum permissible values of superheated/undercooled states for each metal have been determined. The ultimate goal of the study was to determine the temperature dependences of the stationary front velocity υ sℓ (ΔT) describing the SLI mobility in each of the metals in an analytical form. The analytical dependence υ sℓ (ΔT) was constructed by comparing the results of atomistic modeling in the area of maximum permissible superheating/undercooling values with the data of the main kinetic models of Wilson-Frenkel (WF) and Broughton, Gilmer and Jackson (BGJ). An acceptable agreement was achieved by introducing appropriate correction parameters into the kinetic models using the least squares method. The influence of the crystallographic orientation of metals and external pressure on the SLI mobility is investigated.