Numerical modelling of hybrid arc/laser welding: a coupled approach to weld bead formation and residual stresses
Résumé
The joining of high thickness steel sheets by means of hybrid Laser/GMAW welding processes is studied in this paper. A three dimensional finite element model has been developed to simulate this process. Through an ALE framework, a level set approach is used to model the interface between the metal and the surrounding gas. Even though the physics of the plasma is not modelled, both thermal and material supply phenomena are taken into account: (i) The laser and GMAW heat sources are simulated and applied on the interface through the Continuum Surface Force method, (ii) An original method of volume element expansion has been chosen to simulate the material supply and the bead formation. A thermo mechanical problem resolution has been settled in this model. Depending on the thermal evolution of the mechanical parameters and on the velocity field, the material behaviour will be elastic, elasto-visco-plastic or visco-plastic. The ALE approach enables to compute the stresses inside the workpiece and to obtain the displacements of the workpiece borders. Two finite elements models are presented to illustrate: (i) A hybrid arc/laser welding simulation through the thermal and material supply resolution, (ii) A TIG welding simulation through the stress and strain mechanical resolution.
Domaines
MatériauxOrigine | Fichiers produits par l'(les) auteur(s) |
---|
Loading...