Sulphide stress cracking behaviour of the dissimilar metal welded joint of X60 pipeline steel and Inconel 625 alloy

The sulphide stress cracking (SSC) behaviour of the dissimilar metal welded joint of X60 pipeline steel and Inconel 625 alloy in H2S environment was investigated using constant load testing, weight loss.testing and finite element analysis. The dissimilar welded joint shows high SSC susceptibility, and the asymmetric stress concentration after corrosion is the prerequisite for crack initiation. Anodic dissolution prevents crack blunting, whereas hydrogen embrittlement increases the crack propagation rate and affects SSC to propagate along the fusion boundary. (C) 2016 Elsevier Ltd. All rights reserved.