ANALYSIS OF RESIDUAL-STRESSES INDUCED BY LASER PROCESSING

A model for the analysis of residual stresses induced by laser coating s, involving the transition to the liquid state, is presented. The res idual stresses due to the thermal gradient associated with laser harde ning are analysed using a thermo-elastic-plastic finite element comput er code, with isoparametric bidimensional elements in plane strain con ditions. The heating and cooling cycle describing the thermal history was obtained from a previous finite difference thermal model. Since th e complex composite alloys created with the coating have unknown therm omechanical properties, the model was checked for specimens treated wi thout powder injection, for which the residual stresses were measured by X-ray diffraction. The experimental stress results are consistent w ith the calculations.