Tritium Aging Effects on Fracture Toughness of Stainless Steel Weldments
Abstract
The long-term embrittlement effects of tritium and decay helium on the structural properties of stainless steels have been studied for years at Savannah River to provide required data for establishing safe operating conditions and lifetimes of pressure vessels used to contain tritium gas. In this study, the fracture toughness properties of the longest-aged tritium-precharged stainless-steel base metals and weldments tested at Savannah River were measured and compared to earlier results. The fracture toughness values were the lowest recorded here for tritium-exposed stainless steel. As-forged and as-welded specimens were thermally precharging with tritium gas at 34.5 MPa and 623 K, then aged for up to 17 years to buildin decay helium prior to testing. ASTM J-Integral fracture mechanics analyses, transmission electron microscopy (TEM), and small angle neutron scattering (SANS) examinations were conducted to characterize the effects of tritium and its radioactive decay product, helium-3. Results show that the fracture toughness values were reduced to less than 2-4% of the as-forged values for specimens with more than 1300 appm helium from tritium decay. The trend of decreasing fracture toughness values with increasing helium content was consistent with earlier observations, and the data show that Type 304L stainless steel is more resistant tomore »
- Authors:
-
[1];
- Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
- Publication Date:
- Research Org.:
- Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
- Sponsoring Org.:
- USDOE Office of Environmental Management (EM)
- OSTI Identifier:
- 1616263
- Report Number(s):
- SRNL-STI-2019-00249
Journal ID: ISSN 1536-1055; TRN: US2106429
- Grant/Contract Number:
- AC09-08SR22470
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Fusion Science and Technology
- Additional Journal Information:
- Journal Volume: 76; Journal Issue: 3; Journal ID: ISSN 1536-1055
- Publisher:
- American Nuclear Society
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE
Citation Formats
Morgan, Michael J., Hitchcock, Dale A., Krentz, Timothy M., and West, Scott L. Tritium Aging Effects on Fracture Toughness of Stainless Steel Weldments. United States: N. p., 2020.
Web. doi:10.1080/15361055.2019.1704138.
Morgan, Michael J., Hitchcock, Dale A., Krentz, Timothy M., & West, Scott L. Tritium Aging Effects on Fracture Toughness of Stainless Steel Weldments. United States. https://doi.org/10.1080/15361055.2019.1704138
Morgan, Michael J., Hitchcock, Dale A., Krentz, Timothy M., and West, Scott L. Fri .
"Tritium Aging Effects on Fracture Toughness of Stainless Steel Weldments". United States. https://doi.org/10.1080/15361055.2019.1704138. https://www.osti.gov/servlets/purl/1616263.
@article{osti_1616263,
title = {Tritium Aging Effects on Fracture Toughness of Stainless Steel Weldments},
author = {Morgan, Michael J. and Hitchcock, Dale A. and Krentz, Timothy M. and West, Scott L.},
abstractNote = {The long-term embrittlement effects of tritium and decay helium on the structural properties of stainless steels have been studied for years at Savannah River to provide required data for establishing safe operating conditions and lifetimes of pressure vessels used to contain tritium gas. In this study, the fracture toughness properties of the longest-aged tritium-precharged stainless-steel base metals and weldments tested at Savannah River were measured and compared to earlier results. The fracture toughness values were the lowest recorded here for tritium-exposed stainless steel. As-forged and as-welded specimens were thermally precharging with tritium gas at 34.5 MPa and 623 K, then aged for up to 17 years to buildin decay helium prior to testing. ASTM J-Integral fracture mechanics analyses, transmission electron microscopy (TEM), and small angle neutron scattering (SANS) examinations were conducted to characterize the effects of tritium and its radioactive decay product, helium-3. Results show that the fracture toughness values were reduced to less than 2-4% of the as-forged values for specimens with more than 1300 appm helium from tritium decay. The trend of decreasing fracture toughness values with increasing helium content was consistent with earlier observations, and the data show that Type 304L stainless steel is more resistant to tritium-induced cracking than Type 21-6-9 stainless at similar decay helium levels. The fracture toughness properties of long-aged weldments were also affected, but the reductions were not as severe over time because weldments did not retain as much tritium as did the base metals. TEM observations were used to characterize the effects of decay helium bubbles on the deformation substructures, but nanometer-sized helium bubbles were not easily resolved because of high dislocation densities within the forged microstructures. SANS results are presented that suggest the technique can provide information on decay helium bubble size, spacing, and distribution in these steels.},
doi = {10.1080/15361055.2019.1704138},
journal = {Fusion Science and Technology},
number = 3,
volume = 76,
place = {United States},
year = {Fri Apr 24 00:00:00 EDT 2020},
month = {Fri Apr 24 00:00:00 EDT 2020}
}
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Works referenced in this record:
Investigation of microstructural evolution under neutron irradiation in Eurofer97 steel by means of small-angle neutron scattering
journal, April 2009
- Coppola, R.; Lindau, R.; May, R. P.
- Journal of Nuclear Materials, Vol. 386-388
Fast, quantitative, and nondestructive evaluation of hydrided LWR fuel cladding by small angle incoherent neutron scattering of hydrogen
journal, May 2015
- Yan, Y.; Qian, S.; Littrell, K.
- Journal of Nuclear Materials, Vol. 460
Helium bubble evolution in F82H-mod – correlation between SANS and TEM
journal, August 2004
- Coppola, R.; Klimiankou, M.; Magnani, M.
- Journal of Nuclear Materials, Vol. 329-333
Tritium-Helium Effects in Metals
journal, September 1985
- Caskey, G. R.
- Fusion Technology, Vol. 8, Issue 2P2
Tritium and Decay Helium Effects on Cracking Thresholds and Velocities in Stainless Steel
journal, March 2001
- Morgan, Michael J.; Tosten, Michael H.
- Fusion Technology, Vol. 39, Issue 2P2
Fracture toughness of type 304 and 316 stainless steels and their welds
journal, January 1997
- Mills, W. J.
- International Materials Reviews, Vol. 42, Issue 2
Gas densities in he bubbles and their size distribution in nickel measured by neutron scattering
journal, December 1983
- Schwahn, D.; Ullmaier, H.; Schelten, J.
- Acta Metallurgica, Vol. 31, Issue 12
Hydrogen induced ductility losses in austenitic stainless steel welds
journal, February 1981
- Brooks, John A.; West, Anton J.
- Metallurgical Transactions A, Vol. 12, Issue 2