Abstract
The combined effect of thermal aging and irradiation on cast and welded stainless steel solidification structures is not sufficiently investigated. From theory and consecutive aging and irradiation experiments, the effect of simultaneous low rate irradiation and thermal aging is expected to accelerate and modify the aging processes of the ferrite phase. Here, a detailed analysis of long-term aged material at very low fast neutron flux at LWR operating temperatures using Atom Probe Tomography is presented. Samples of weld material from various positions in the core barrel of the Zorita PWR are examined. The welds have been exposed to 280–285 °C for 38 years at three different neutron fluxes between 1 × 10−5 and 7 × 10−7 dpa/h to a total dose of 0.15–2 dpa. The aging of the ferrite phase occurs by spinodal decomposition , clustering and precipitation of e.g. G-phase. These phenomena are characterized and quantitatively analyzed in order to understand the effect of flux in combination with thermal aging.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
J. Zhou, J. Odqvist, M. Thuvander, P. Hedström, Quantitative evaluation of spinodal decomposition in Fe–Cr by atom probe tomography and radial distribution function analysis. Microsc. Microanal. 19, 665–675 (2013)
T. Takeuchi, J. Kameda, Y. Nagai, T. Toyama, Y. Matsukawa, Y. Nishiyama, K. Onizawa, Microstructural changes of a thermally aged stainless steel submerged arc weld overlay cladding of nuclear reactor pressure vessels J. Nucl. Mat. 425, 60–64 (2012)
C. Pareige, S. Novy, S. Saillet, P. Pareige, Study of phase transformation and mechanical properties evolution of duplex stainless steels after long term thermal ageing (>20 years). J. Nucl. Mater. 411(1–3), 90–96 (2011)
M. Bjurman, M. Thuvander, F. Liu, P. Efsing, Phase separation study of in-service thermally aged cast stainless steel—Atom probe tomography, in: Proceedings of the 17th International Symposium on Environmental Degradation of Materials in Nuclear Power Systems, CNS 2015
A. Heinrich, T. Al-Kassab, R. Kirchheim, Investigation of the early stages of decomposition of Cu/0.7 at.% Fe with the tomographic atom probe. Mat. Sci. Eng. A353 (2003) 92_/98
D. Vaumousse, A. Cerezo, P.J. Warren, A procedure for quantification of precipitate microstructures. Ultramicroscopy 95, 215–221 (2003)
J.M. Hyde, C.A. English, An analysis of the structure of irradiation induced Cu-enriched clusters in low and high Nickel welds, Materials Research Society Symposium, 2000, pp. R6.6.1–R6.6.12. Boston
Acknowledgements
The authors wish to express their sincere gratitude to Mr. Roger Lundström, who performed specimen extraction and light optical microscopy, and Anders Jenssen for fruitful discussions, both from Studsvik Nuclear AB. EPRI have kindly allowed use of the material. The work was funded by the Swedish Radiation Safety Authority, the Swedish NPPs Materials Group (SUMG) and Studsvik Nuclear AB.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2019 The Minerals, Metals & Materials Society
About this paper
Cite this paper
Bjurman, M., Lindgren, K., Thuvander, M., Ekström, P., Efsing, P. (2019). Microstructural Evolution of Welded Stainless Steels on Integrated Effect of Thermal Aging and Low Flux Irradiation. In: Jackson, J., Paraventi, D., Wright, M. (eds) Proceedings of the 18th International Conference on Environmental Degradation of Materials in Nuclear Power Systems – Water Reactors. The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-030-04639-2_130
Download citation
DOI: https://doi.org/10.1007/978-3-030-04639-2_130
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-030-04638-5
Online ISBN: 978-3-030-04639-2
eBook Packages: Chemistry and Materials ScienceChemistry and Material Science (R0)