Synchrotron XRD Evaluation of Residual Stresses Introduced by Laser Shock Peening for Steam Turbine Blade Applications

Synchrotron XRD Evaluation of Residual Stresses Introduced by Laser Shock Peening for Steam Turbine Blade Applications

M. Newby, A. Steuwer, D. Glaser, C. Polese, D.G. Hattingh, C. Gorny

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Steam turbines used in the power generation industry are subject to fatigue during normal operation which includes transient events such as start-ups and steady state operation. Surface treatment methods, such as shot peening (SP) and roller burnishing, to induce surface compressive residual stresses in critical areas and improve fatigue life are commonly used, but the depth of the induced residual stresses is limited by the process. Laser shock peening (LSP) is a more recent development that has been applied in the aerospace industry on titanium blades, but is not yet commonly used in the power generation industry. The current research is focused on optimizing LSP parameters for the application of the process on 12Cr steels used for turbine blades. Evaluation of the induced residual stress was done with both conventional laboratory X-ray diffraction (XRD) and synchrotron X-ray diffraction (SXRD) techniques.

Keywords
Laser Shock Peening, Residual Stress, Synchrotron, Diffraction

Published online 4/20/2018, 6 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: M. Newby, A. Steuwer, D. Glaser, C. Polese, D.G. Hattingh, C. Gorny, ‘Synchrotron XRD Evaluation of Residual Stresses Introduced by Laser Shock Peening for Steam Turbine Blade Applications’, Materials Research Proceedings, Vol. 4, pp 97-102, 2018

DOI: http://dx.doi.org/10.21741/9781945291678-15

The article was published as article 15 of the book

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] M. Newby, M. N. James and D. G. Hattingh, Finite element modelling of residual stresses in shot-peened steam turbine blades, Fatigue Fract. Eng. Mater. Struct., 37(7) (2014) 707–716. https://doi.org/10.1111/ffe.12165
[2] M. Newby, D. Glaser, and C. Polese, Laser Shock Peening Process Development for Turbine Blade Refurbishment Applications Using a Commercial ‘ Mid-Range ’ Energy Laser, in 6th International Conference on Laser Peening and Related Phenomena, 2016.
[3] K. R. Kuveya, C. Polese and M. Newby, Laser Peening versus Shot Peening Effects on Residual Stress and Surface Modification of X12CrNiMo12 Turbine Blade, in 6th International Conference on Laser Peening and Related Phenomena, 2016.