Creep Behaviour of Full‐size Welded Joints: Defect Acceptance Criteria

Abstract

In order to explore the creep crack growth behaviour in welds of real components, creep tests were performed at 600 °C on large specimens made of 316L(N) stainless steel plates. Manual Metal Arc (MMA) welds were investigated. The overall deformation of the specimens, and in many instances the local deformations of the welds, were recorded. The evolutions of the defects were followed by potential drop techniques. The experimental results were compared with two‐dimensional finite element computations, based on the creep behaviour of the base and weld metals, determined with small standard specimens. The time to creep crack growth initiation was correlated with the C* parameter determined from the load–displacement rate. The times to initiation of creep crack growth were compared with evaluations using the RCC‐MR code and R5 rules, as well as other methods, in particular those derived by finite elements analysis