Ab Initio Nonequilibrium Thermodynamic and Transport Properties of Ultrafast Laser Irradiated 316L Stainless Steel

Abstract

We present calculations of transient behavior of thermodynamic and transport coefficients on the time scale of electron–phonon relaxation upon ultrashort laser excitation of ferrous alloys. Their role defining energy deposition and primary microscopic material response to the laser irradiation is outlined. Nonequilibrium thermodynamic properties of 316L stainless steel are determined from first-principles calculations. Taking into account the complexity of multimetallic materials, the density functional theory is first applied to describe the electronic density of states of an alloy stainless steel matrix as a function of electronic heating. An increase of the localization degree of the charge density was found to be responsible for the modification of the electronic structure upon electronic heating, with consequences on chemical potential, electronic capacity, and pressure. It is shown that the electronic temperature dependence of stainless steel thermodynamic properties are consistent with the behavior...