FE simulation of laser curve bending of sheet metals

Laser bending is a highly flexible sheet metal forming technique. For the production of complex shaped or spatially curved parts, it is more convenient and efficient to apply curved irradiation paths instead of linear paths. In this paper, a finite element model of heat flux based on scanning path described with B-spline curve was built. Then, FE simulation of laser beam scanning on the forming sheet metals was carried out. And transient temperature fields, displacement fields, stress fields and strain fields were investigated. The proposed model can be used to forecast laser curve bending of sheet metal conveniently. The simulated results show that: (1) there is a good agreement between the FE simulations based on the proposed model and the experiments; (2) the peak temperatures of the upper surface increase when the laser power or the path curvature increases, but decrease when the laser spot diameter or the scanning velocity increases. The peak temperatures increase roughly when the laser energy density increases; (3) the laser curve bending produces a significant change of distortion under the same conditions of deformation. The warped curvature increases when the laser energy density or the path curvature increases.