Numerical simulation of temperature rise of material surface irradiated by the laser

In order to load laser energy reasonably in the laser ultrasonic testing under the ablation mechanism and obtain large amplitude of ultrasonic signal without damaging the detected material, temperature rise and laser ablation of material surface irradiated by laser were analyzed. Theory model of laser irradiating material surface was established and laser was loaded on the material surface by the form of heat flux. By combining heat conduction differential equation with the boundary condition of convective heat transfer and radiation heat transfer, the latent heat in the material surface during the heating process was dealt with effectively and numerical simulation of temperature field of material surface irradiated by laser was made. The program flow of laser ablating material finite element analysis was given out. Taking 45# billet for example, laser irradiation simulation was made. The temperature rise law of the nodes of the irradiated area, of the lower area and near the boundary was analyzed. Contrasting with the actual ablation by laser irradiation and collecting the laser ultrasonic signal, the verification was made. The results show that numerical simulation provides the basis for the load during the finite element thermal stress analysis and the reference for the loading of the laser energy during the laser ultrasonic test.