Laser Induced Thermal Stresses in Solids: Exponentially Time Decaying Pulse Case
B.S. Yilbas and N. Al-Aqeeli
Laser heating of solids results in thermal expansion of the region irradiated by the laser beam. Depending on the intensity and duration of the laser pulse, the thermal stress levels developed in this vary. In the present study, laser heating of a solid is investigated and analytical solutions for temperature and stress fields within the solid are presented. In the analysis, an exponentially decaying pulse is treated and the Laplace Transformation method used to obtain the closed form solutions. It is found that the temperature rises rapidly in the early stage of heating as the internal energy gain is greater than the diffusional energy loss from the heated surface into the bulk solid. The thermal stress waves generated propagate towards the solid bulk and the stress level behind the wave is tensile whereas it is compressive after it.