Experimental Mechanics

, Volume 29, Issue 1, pp 54–57 | Cite as

Residual stresses in reverse-bend test samples for stress-corrosion testing

  • C. O. Ruud
  • D. J. Snoha
  • A. R. Mcllree
Article
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Abstract

Cracking of Inconel Alloy 600 (registered trademark) u-bend tubes used in pressure-water-reactor (PWR) steam generators has been a major concern in the nuclear-power industry over the past several years. The mechanism of cracking has been determined to be intergranular stress-corrosion cracking with residual stresses a major contributor. A simple specimen known as a reverse u-bend (RUB) has been used by a number of laboratories to simulate the high stresses and plastic strain extant in the most susceptible regions of the u-bend tubes. This paper presents the results of residual-stress measurements on four RUB samples, each from a different laboratory.

The results indicate that the individual RUB fabrication procedures used by different laboratories tend to produce different residual-stress patterns in the highly strained regions over 700 tensile to nearly 700-MPa compressive on different samples. Stress gradients on the order of 140 MPa/mm were found on some samples. The residual-stress patterns were seen to qualitatively predict the stress-corrosion-cracking pattern experienced on similar samples.

Keywords

Steam Plastic Strain Steam Generator Stress Gradient Strained Region 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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Copyright information

© Society for Experimental Mechanics, Inc. 1989

Authors and Affiliations

  • C. O. Ruud
    • 1
  • D. J. Snoha
    • 1
  • A. R. Mcllree
    • 1
  1. 1.Materials Research LaboratoryThe Pennsylvania State UniversityUniversity Park

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