K/J value estimation of specimen extracted from mock-ups containing dissimilar metal welds

The work presented in this paper is part of the contribution of the Joint Research Centre (JRC) Petten, Netherlands to the European Commission funded R&D project MULTIMETAL. The objectives of the project are the development of a standard for fracture resistance testing of multi-metallic specimens and the development of harmonized procedures for dissimilar metal welds (DMWs) for brittle and ductile integrity assessment. Part of the project is a benchmark exercise involving elastic-plastic finite element (FE) analyses on standard fracture testing specimens to determine J integral values and η factors to accompany the fracture test program of the project. The benchmark exercise is performed in two stages. In the first stage FE analyses on homogenous specimens, which are entirely made of ferritic steel 18MND5 have been performed. The performed FE analyses involve CT12.5, SENB20 and SENT22 specimens and the obtained results for η factors show a very good agreement with values of codes and standards (ASTM E1820-09, DNV-RP-F108). Within the second stage of the benchmark exercise first FE analyses on multi-metallic CT12.5 specimens resembling three different crack locations one of the weld mock-ups used in the project have been performed. The first results of the second stage show that the η factor level for the multi-metallic specimen is generally higher than for corresponding homogeneous specimen.

MARTIN Oliver;  MACHINA Gangadhar;  SIMONOVSKI Igor; 

2013-12-19

Nuclear Society of Slovenia

JRC84072

978-961-6207-36-2,   

https://publications.jrc.ec.europa.eu/repository/handle/JRC84072,