Determination of the Residual Stresses Near the Ends of Skip Welds Using NeutronDiffraction and X-ray Diffraction Procedures

摘要

Welding is known to be a significant factor in the formation of residualstresses. Residual stresses are suspected as the reason for the occurrence of leaks in some railroad tank cars that had stiffeners welded to them. Residual stresses at the surface and in the bulk of metals can be measured non-destructively by x-ray and neutron diffraction respectively. In this report the results of such non-destructive residual stress measurements on one-pass, skip, bead-on plate welds are presented. The plate specimens used for this investigation contained two beads that represent the skip weld process. Of the full weld bead only positions close to the end of the first and the start of the second bead are investigated. The results show longitudinal tensile stresses and compressive transverse and perpendicular residual stresses in the region close to both the weld end and the weld start.