Effect of employing buffer layer in repaired dissimilar welded joints on the residual stresses based on contour and slitting methods

Abstract

The residual stresses (RS) contribute to the integrity of the welded joint. In some cases, such as repaired dissimilar joints, this factor is crucial. The longitudinal (hoop) and transverse residual stresses of three chromium-molybdenum steel (A387 Grade 11)/austenitic steel (AISI 304) dissimilar welded repair mockups were measured in this study. The first and second repair mockups used ENiCrMo-3 and ENiCrFe-3 (conventional procedures), while the third repair mockup used ENi-1 as a buffer layer plus ENiCrFe-3. The contour method was used to measure longitudinal RS, and the slitting method was used to measure transverse RS. The buffer layer procedure resulted in lower longitudinal stresses at the interior regions of the repair than the other two procedures. The first, second, and third mockups showed transverse RS lower than the yield strength of the corresponding metals, with peak tensile stresses of 279, 113, and 230 MPa, respectively.