Residual Stress Analysis in Girth-welded Ferritic and Austenitic Steel Pipes Using Neutron and X-Ray Diffraction

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Residual Stress Analysis in Girth-welded Ferritic and Austenitic Steel Pipes Using Neutron and X-Ray Diffraction

N. Hempel, J.R. Bunn, T. Nitschke-Pagel, E.A. Payzant, K. Dilger

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Abstract. This paper is dedicated to the thorough experimental analysis of the residual stresses in the vicinity of tubular welds and the mechanisms involved in their formation. Pipes made of a ferritic-pearlitic structural steel and an austenitic stainless steel are each investigated in this study. The pipes feature a similar geometry and are welded with two passes and comparable parameters. Residual strain mappings are carried out using X-ray and neutron diffraction. The combined use of both techniques permits both near-surface and through-wall analyses of the residual stresses. The findings allow for a consistent interpretation of the mechanisms accounting for the formation of the residual stress fields due to the welding process. Since the results are similar for both materials, it can be concluded that residual stresses induced by phase transformations, which can occur in the structural steel, play a minor role in this regard.

Keywords
Welding, Residual Stress, Tubes and Pipes, Ferritic Steel, Austenitic Steel, Neutron Diffraction, X-Ray Diffraction

Published online 12/22/2016, 6 pages
Copyright © 2016 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: N. Hempel, J.R. Bunn, T. Nitschke-Pagel, E.A. Payzant, K. Dilger, ‘Residual Stress Analysis in Girth-welded Ferritic and Austenitic Steel Pipes Using Neutron and X-Ray Diffraction’, Materials Research Proceedings, Vol. 2, pp 229-234, 2017

DOI: http://dx.doi.org/10.21741/9781945291173-39

The article was published as article 39 of the book Residual Stresses 2016

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

References
[1] A.F. Hobbacher, Recommendations for Fatigue Design of Welded Joints and Components, second ed., Springer, Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-319-23757-2
[2] P.J. Bouchard, Validated residual stress profiles for fracture assessments of stainless steel pipe girth welds, Int. J. Press. Ves. Pip. 84 (2007) 195–222. http://dx.doi.org/10.1016/j.ijpvp.2006.10.006
[3] S. Song, P. Dong, J. Zhang, A full-field residual stress estimation scheme for fitness-for-service assessment of pipe girth welds: Part 1, Int. J. Press. Ves. Pip. 126-127 (2015) 58–70. http://dx.doi.org/10.1016/j.ijpvp.2015.01.002
[4] N. Hempel, T. Nitschke-Pagel, K. Dilger, Residual stresses in multi-pass butt-welded tubular joints, Adv. Mat. Res. 996 (2014) 488-493.
[5] N. Hempel, T. Nitschke-Pagel, K. Dilger, Residual stresses in multi-pass butt-welded ferritic-pearlitic steel pipes, Weld. World 59 (2015) No. 4 555-563.
[6] N. Hempel, T. Nitschke-Pagel, K. Dilger, Study on the near-surface residual stress state in butt-welded pipes of austenitic steel using X-ray diffraction, Weld. World (accepted 19/08/2016, DOI 10.1007/s40194-016-0378-9).
[7] W. Woo, V. Em, C.R. Hubbard, H.J. Lee, K.S. Park, Residual stress determination in a dissimilar weld overlay pipe by neutron diffraction, Mat. Sci. Eng. A 528 (2011) 8021-8027. http://dx.doi.org/10.1016/j.msea.2011.07.059
[8] M.T. Hutchings, P.J. Withers, T.M. Holden, T. Lorentzen, Introduction to the Characterization of Residual Stress by Neutron Diffraction, CRC Press, Boca Raton, 2005.