Abstract
Cast duplex stainless steel piping in light water nuclear reactors experience thermal aging embrittlement during operational service. Interest in extending the operational life to 80 years requires an increased understanding of the microstructural evolution and corresponding changes in mechanical behavior. We analyze the evolution of the microstructure during thermal aging of cast CF-3 and CF-8 stainless steels using electron microscopy and atom probe tomography. The evolution of the mechanical properties is measured concurrently by mechanical methods such as tensile tests, Charpy V-notch tests, and instrumented nanoindentation. A microstructure-based finite element method model is developed and utilized in conjunction with the characterization results in order to correlate the local stress-strain effects in the microstructure with the bulk measurements. This work is supported by the DOE Nuclear Energy University Programs (NEUP), contract number DE-NE0000724.
References
T.S. Byun, Y. Yang, N.R. Overman, J.T. Busby, Thermal aging phenomena in cast duplex stainless steels. JOM 68, 507–516 (2016)
O.K. Chopra, W.J. Shack, Mechanical properties of thermally aged cast stainless steels from shippingport reactor components. U.S. Nuclear Regulatory Commission, Argonne National Laboratory (1995)
S. Li, Y. Wang, S. Li, H. Zhang, F. Xue, X. Wang, Microstructures and mechanical properties of cast austenite stainless steels after long-term thermal aging at low temperature. Mater. Des. 50, 886–892 (2013)
K.H. Lo, C.H. Shek, J.K.L. Lai, Recent developments in stainless steels. Mater. Sci. Eng. R 65, 39–104 (2009)
S. Ankem, H. Margolin, C.A. Greene, B.W. Neuberger, P.G. Oberson, Mechanical properties of alloys consisting of two ductile phases. Prog. Mater. Sci. 51, 632–709 (2006)
C.A. Greene, S. Ankem, Modelling of elastic interaction stresses in two-phase materials by FEM. Mater. Sci. Eng. A 202, 103–111 (1995)
P.H. Pumphrey, K.N. Akhurst, Aging kinetics of CF3 cast stainless steel in temperature range 300–400 °C. Mater. Sci. Technol. 6, 211–219 (1990)
L.F. Ramos, D.K. Matlock, G. Krauss, On the deformation behavior of dual-phase steels. Metall. Trans. A 10, 259–261 (1979)
S. Mburu, R.P. Kolli, D.E. Perea, S.C. Schwarm, A. Eaton, J. Liu, S. Patel, J. Bartrand, S. Ankem, The M 23 C 6 Carbide Phase and Spinodal Decomposition in Unaged CF-3 and CF-8 Cast Duplex Stainless Steels (submitted for review, 2016)
H.M. Chung, O.K. Chopra, Microstructures of Cast-Duplex Stainless Steel After Long-Term Aging, in Proceedings of 2nd International Symposium on Environmental Degradation of Materials in Nuclear Power Systems—Water Reactors, American Nuclear Society, Monterey, CA (1985), pp. 287–292
P.D. Southwick, R.W.K. Honeycombe, Met. Sci. 16, 475–482 (1982)
S.C. Schwarm, R.P. Kolli, E. Aydogan, S. Mburu, S. Ankem, Characterization of phase properties and deformation in ferritic-austenitic duplex stainless steels by nanoindentation and finite element method. Mater. Sci. Eng. A 680, 359–367 (2017)
Acknowledgements
This work is funded by the U.S. Department of Energy Nuclear Energy University Program (DOE-NEUP); technical monitor Dr. Jeremy T. Busby, Oak Ridge National Laboratory; contract number DOE-NE0000724. Mr. Schwarm would like to acknowledge the Department of Energy: Office of Nuclear Energy (DOE-NE) Integrated University Program (IUP) fellowship program for support. Ms. Sarah Mburu is partially supported by the National Science Foundation (NSF) Louis Stokes Alliances for Minority Participation (LSAMP) under Grant No. 0833018. We would also like to thank Dr. Robert Bonenberger and Dr. Aldo Ponce of the Modern Engineering Materials Instructional Laboratory (MEMIL) at the University of Maryland for access and assistance with the nanoindenter and sample preparation equipment. The APT experiments were conducted using EMSL, a national scientific user facility sponsored by the Department of Energy’s Office of Biological and Environmental Research located at PNNL.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2017 The Minerals, Metals & Materials Society
About this paper
Cite this paper
Schwarm, S.C., Mburu, S., Kolli, R.P., Perea, D.E., Liu, J., Ankem, S. (2017). Mechanical and Microstructural Effects of Thermal Aging on Cast Duplex Stainless Steels by Experiment and Finite Element Method. In: Charit, I., Zhu, Y., Maloy, S., Liaw, P. (eds) Mechanical and Creep Behavior of Advanced Materials. The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-319-51097-2_20
Download citation
DOI: https://doi.org/10.1007/978-3-319-51097-2_20
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-51096-5
Online ISBN: 978-3-319-51097-2
eBook Packages: Chemistry and Materials ScienceChemistry and Material Science (R0)