Novel images of the evolution of stress corrosion cracks from corrosion pits

Research output: Contribution to journalArticle

Authors

Colleges, School and Institutes

Abstract

SCC in turbine disc steels exposed to simulated steam-condensate tends to nucleate preferentially from corrosion pit precursors. The evolution of these cracks is not straightforward and not well understood. In this work, unique three-dimensional X-ray microtomographic images have confirmed that cracks develop predominantly at the shoulder of the pit, near the pit/surface interface, for specimens stressed to 50-90% sigma(0.2). In support of this observation, FEA of model pits indicate that strain is a maximum on the pit wall just below the pit mouth. Implications of these observations for the pit-to-crack transition and predictive-modelling of crack nucleation and growth are discussed. (C) 2011 Elsevier Ltd. All rights reserved.

Details

Original languageEnglish
Pages (from-to)3466-3485
Number of pages20
JournalCorrosion Science
Volume53
Issue number11
Publication statusPublished - 1 Nov 2011

Keywords

  • Stress Corrosion, Low alloy steel, Pitting corrosion