NON DESTRUCTIVE RESIDUAL-STRESS ANALYSIS IN THE BULK OF COLD FORWARD EXTRUDED COMPONENTS

After cold forward extrusion of steel samples, the texture and the def ormation-induced residual stresses were analysed by X-ray and neutron diffraction, The results reveal a [110] fibre texture. The difference between the mean stresses in axial and radial direction within the rod kernel is negative and decreases with increasing degree of natural st rain. The choice of the die opening angle does not have a significant influence on the residual stress state within the rod kernel. Furthero n there is no significant difference of the residual stress state in s amples of the steel grades C15 compared to 16MnCr5. The amount of comp ressive residual stresses within the rod kernel can be substantially r educed by election of the sample.