Numerical investigation of the residual stresses in strength-mismatched dissimilar steel butt welds

Abstract

The presence of residual stresses in and around the welds can be detrimental to the performance of the welded part. Therefore, a good estimation of residual stresses in welds is needed. Simulation tools based on the finite element (FE) method are very useful to predict welding residual stresses. However, the numerical simulation of residual stresses in dissimilar steel welds is generally more challenging than that of residual stresses in similar steel welds because of the difference in the mechanical properties of the base metals to be joined and the weld metal strength mismatch which lies between two different base metals resulting from the use of weld metal fitted to either one. This paper presents the characteristics of residual stresses in strength-mismatched dissimilar steel butt welds by carrying out three-dimensional thermal elastic-plastic FE analysis, and the effects of weld metal strength on residual stress distributions are further investigated on the basis of the FE analysis results. Moreover, residual stresses in strength-mismatched similar steel butt welds are examined for comparison.