Thermometallurgical modeling applied to laser welding of steels

The thermal modeling of a structure whose local composition depends on temperature requires the coupled resolution of the heat conduction equation and the equations describing the transformation kinetics of the phases constituting the base material. SYSWELD+ code, which permits this coupled solution, has been applied to the modeling of the welding of steel under LASER beam. The aim is to reach the local and instantaneous temperatures, phases proportions and strains generated by such a severe process. The simulation has been completed with experimental investigations (thermal evolutions, residual strain, structural micrographies, H.A.Z., etc.). The good accordance observed between the calculation and the experimental results gives the model an interesting behaviour for the prediction of industrial devices involving heat treatments (welding being an example). (C) 2001 Editions scientifiques et medicales Elsevier SAS.