Temperature dependent determination of electron heat capacity and electron-phonon factor for Fe$_{0.72}$Cr$_{0.18}$Ni$_{0.1}$

TL;DR

This study uses ab initio calculations to determine how electron heat capacity and electron-phonon coupling in FeCrNi alloy vary with temperature, aiding laser-material interaction modeling.

Contribution

It provides the first temperature-dependent predictions of electron heat capacity and electron-phonon factor for FeCrNi alloy using relativistic ab initio methods.

Findings

Maximum 5% deviation in electron heat capacity compared to pure Fe.

Maximum 25% deviation in electron-phonon coupling factor compared to pure Fe.

Results support improved two-temperature model simulations for the alloy.

Abstract

A theoretical approach using ab initio calculations has been applied to study the interaction of an ultra-short laser pulse with the metal alloy Fe$_{0.72}$Cr$_{0.18}$Ni$_{0.1}$ (AISI 304). The electronic structure is simulated by taking into account the chemical and magnetic disorder of the alloy by the coherent potential approximation implemented in a fully relativistic Korringa-Kohn-Rostoker-formalism in the framework of spin density functional theory. Utilizing these predictions we determined the electron heat capacity and the electron-phonon coupling factor of Fe$_{0.72}$Cr$_{0.18}$Ni$_{0.1}$ in dependence on the electron temperature for two-temperature model applications. Compared with pure Fe a maximum deviation of 5~\% for the electron heat capacity and 25~\% for the electron-phonon coupling factor is found.