Numerical simulation of Energy effects in laser bending of thick steel plate

Temperature gradient across the thickness is the main driving force for laser bending of thick plate. The influence of Energy parameters on temperature gradient is significant. In this paper, the effect of laser power, scanning speed, laser spot and number of scanning passes has been studied for laser bending of thick steel plate. A three-dimensional FEM simulation was proposed, which included a non-linear transient coupled thermal-mechanical analysis accounting for the temperature dependency of the thermal and mechanical properties of the material. The temperature field and bending angle have been obtained from the simulation. Temperature gradient and bending angle are increased with the increase of laser power and decreased with the increase of scanning speed and laser spot. The temperature distribution is similar between each irradiation. And bending angle increases almost linearly with the increasing number of irradiations during multiple-irradiation laser bending process. The measurement of temperature and bending angle was carried out. Good agreement between simulation results and experiment results is demonstrated.