Material response to thermal loading due to short pulse laser heating

The laser-induced thermal stresses are important during heating of substrat e surfaces, since stress levels above the yield stress of the substrate mat erial occur. In this case, the plastic deformation and/or material defects occur in the irradiated region. In the present study, laser short pulse hea ting of gold is considered. The electron kinetic theory approach is employe d to model the heating process. This approach accounts for the non-equilibr ium energy transport in the surface vicinity of the substrate material. The thermal analysis and temperature predictions from an electron kinetic theo ry approach were presented in a previous study. Therefore, the results of t hermo-elastic analysis due to the temperature field predicted in the previo us study are given here. The elastic stresses developed in the substrate ma terial due to the temperature field are modelled, and the temporal and spat ial variations of the stress field and von Mises stresses are computed. It is found that the stress field in the substrate material does not follow th e temperature field. A stress level on the order of 10(9) Pa occurs in the surface vicinity. (C) 2001 Elsevier Science Ltd. All rights reserved.