MEASUREMENT OF RESIDUAL STRESSES IN THICK SECTION STEEL ELECTRON BEAM WELDS

Residual stresses were measured and predicted in steel electron beam welded samples, one supplied by Rolls-Royce, UK, and a second by CEA, France. In the case of the Rolls-Royce sample, measurements were made before and after post-weld heat treatment. The deep hole drilling technique was applied to obtain measurements across and through the EB welds. It is shown that the tensile residual stresses are confined to a region either side of the EB weld that corresponds to about 20% of the wall thickness. Post-weld heat treatment is shown to substantially reduce the magnitudes of the peak residual stresses. Comparisons between measurements and predicted residual stresses in the Rolls-Royce sample show that predicted hoop stresses are substantially greater than measured although there is a fair comparison between measured and predicted radial stresses.