Residual stress predictions on a 29" narrow gap dissimilar metal weld and comparison with a 14" configuration

AREVA has developed narrow gap weld techniques to perform junctions between low alloy steel heavy section components and austenitic stainless steel piping systems. In parallel, for a good understanding of welding and post weld heat treatment consequences, numerical welding simulation has already demonstrated its relevance to predict residual stress fields in welded components [1]. This paper presents Finite Element (FE) simulations of a 29" multipass narrow gap Dissimilar Metal Weld (DMW) configuration, the welding simulation including non linear kinematic hardening models, phase transformations and viscoplastic calculations for reproducing the post weld heat treatment. The numerical results are compared to measurements obtained by the deep hole drilling technique [2]. This work gives another evidence of the relevance of the numerical welding simulation. Particularly, the comparison with a 14" configuration [3] gives some elements to assess on the validity of both numerical and experimental techniques and on the weld thickness effect.