Short-pulse laser heating of gold-chromium layers: Thermo-elasto-plastic analysis

In this paper, laser short-pulse heating of gold-chromium two-layer assembly is considered. Since, the heating period is in the order of picoseconds, nonequilibrium energy transport is considered when modelling the heating process. An electron kinetic theory is employed to derive the governing equations of energy transport while elasto-plastic analysis is carried out when modelling the thermomechanical response of the substrate materials. In the analysis, thermomechanical coupling is considered and it is accommodated in the energy transport equation. A numerical method using a finite difference scheme is used to discretize the governing equations. It is found that temperature attains considerably high values across the gold-chromium interface, which in turn results in excessive stress levels in this region.