Modelling of residual stresses during laser cutting of small-diameter holes

Laser hole cutting in a sheet metal is modelled, and temperature as well as the stress fields developed around the hole circumference are examined. The finite element method is used to predict the temperature and stress fields during and after completion of the cutting process. An experiment resembling the simulation conditions is carried out and the residual stress developed in the cutting region is measured using the X-ray diffraction (XRD) technique. It is found that the principal stresses are tensile in the region close to the hole surface, and the stress components become compressive as the distance from the hole surface to the solid bulk increases. The residual stress predicted agrees with the measured data.