Influence of interference effects in oxide films on the kinetics of laser heating of metals

Abstract

A theoretical model is developed for the oxidation of metals by cw laser radiation allowing for interference effects in the oxide film. The problem is resolved by jointly solving a parabolic equation for the metal oxidation kinetics, a heat conduction equation allowing for convective and radiative losses, and also an equation which relates the absorbtivity of the oxide-metal system to the thickness and optical constants of the oxide film and the cold absorptivity of the metal. An analysis is made of the heating kinetics from room temperature to the melting point of a thermally thin plate and a semi-infinite target. The results of the calculations show good agreement with the experimental data on the oxidation of copper by cw CO2 laser radiation.