Conference Paper

LARGE DUCTILE TEARING IN DISSIMILAR MATERIAL WELDS AND TRANSFERABILITY ISSUES

Conference: PVP2011

ABSTRACT Dissimilar Metal Welds (DMW) are required in nuclear reactors to join low alloy steel components and stainless piping. The thermal and mechanical mismatch between the dissimilar material characteristics favors the stress concentration in the weld along the austenitic/ferritic interface. Assessing the ductile tearing resistance of DMWs is an issue even for crack initiation. But predicting large crack extensions is even more difficult for several reasons: crack path deviation, J-R curve determination, transferability from specimen to structures. This paper presents an approach to determine the resistance curve of a DMW on the basis of a ductile tearing simulation using a cavity growth model.

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May 22, 2014