scholarly journals Water corrosion of spent nuclear fuel: radiolysis driven dissolution at the UO2/water interface

2015 ◽  
Vol 180 ◽  
pp. 301-311 ◽  
Author(s):  
Ross Springell ◽  
Sophie Rennie ◽  
Leila Costelle ◽  
James Darnbrough ◽  
Camilla Stitt ◽  
...  

X-ray diffraction has been used to probe the radiolytic corrosion of uranium dioxide. Single crystal thin films of UO2 were exposed to an intense X-ray beam at a synchrotron source in the presence of water, in order to simultaneously provide radiation fields required to split the water into highly oxidising radiolytic products, and to probe the crystal structure and composition of the UO2 layer, and the morphology of the UO2/water interface. By modeling the electron density, surface roughness and layer thickness, we have been able to reproduce the observed reflectivity and diffraction profiles and detect changes in oxide composition and rate of dissolution at the Ångström level, over a timescale of several minutes. A finite element calculation of the highly oxidising hydrogen peroxide product suggests that a more complex surface interaction than simple reaction with H2O2 is responsible for an enhancement in the corrosion rate directly at the interface of water and UO2, and this may impact on models of long-term storage of spent nuclear fuel.

2005 ◽  
Vol 93 (3) ◽  
Author(s):  
Bruce McNamara ◽  
Brady D. Hanson ◽  
Edgar C. Buck ◽  
Chuck Soderquist

SummaryImmersing commercial spent nuclear fuel (CSNF) in deionized water produced two corrosion products after a 2-year contact period. Suspensions of aggregates were observed to form at the air–water interface for each of five samples. These suspended aggregates were characterized by X-ray diffraction (XRD) to be metastudtite (UO


2013 ◽  
Vol 1514 ◽  
pp. 125-130
Author(s):  
Axel Richard ◽  
Etienne Castelier ◽  
Herve Palancher ◽  
Jean-Sebastien Micha ◽  
Philippe Goudeau

Abstract:In the framework of the study of long-term storage of the spent nuclear fuel, polycrystalline UO2 samples have been implanted with He ions. The thin implanted layer, close to the free surface is subjected to elastic stresses which are studied by x-ray diffraction (micro Laue diffraction) and a mechanical modeling. A simple expression of the displacement gradient tensor has been evidenced; it concerns only three terms (ε3, ε4 and ε5) which strongly evolve with considered grain orientations. Finally, we show that results obtained with micro diffraction are in very good agreement with conventional x-ray diffraction measurements done in laboratory at macro scale.


2012 ◽  
Vol 1518 ◽  
pp. 111-116 ◽  
Author(s):  
Martin C. Stennett ◽  
Daniel J. Backhouse ◽  
Colin L. Freeman ◽  
Neil C. Hyatt

ABSTRACTTechnetium-99 (99Tc) is a fission product produced during the burning of nuclear fuel and is particularly hazardous due to its long half life (210000 years), relatively high content in nuclear fuel (approx. 1 kg per ton of SNF), low sorption, and high mobility in aerobic environments. During spent nuclear fuel (SNF) reprocessing Tc is released either as a separate fraction or in complexes with actinides and zirconium. Although Tc has historically been discharged into the marine environment more stringent regulations mean that the preferred long term option is to immobilise Tc in a highly stable and durable matrix. This study investigated the feasibility of incorporating of Mo (as a Tc analogue) in a crystalline host matrix, synthesis by solid state synthesis under different atmospheres. Samples have been characterised with X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray absorption spectroscopy (XAS).


2007 ◽  
Vol 2007 (suppl_26) ◽  
pp. 229-234 ◽  
Author(s):  
V. A. Chernenko ◽  
S. Doyle ◽  
M. Kohl ◽  
P. Müllner ◽  
S. Besseghini ◽  
...  

2009 ◽  
Vol 385 (2) ◽  
pp. 449-455 ◽  
Author(s):  
H. Palancher ◽  
N. Wieschalla ◽  
P. Martin ◽  
R. Tucoulou ◽  
C. Sabathier ◽  
...  

2017 ◽  
Vol 153 ◽  
pp. 07035 ◽  
Author(s):  
Mikhail Ternovykh ◽  
Georgy Tikhomirov ◽  
Ivan Saldikov ◽  
Alexander Gerasimov

Author(s):  
Poh-Sang Lam ◽  
Robert L. Sindelar

A typical multipurpose canister (MPC) is made of austenitic stainless steel and is loaded with spent nuclear fuel assemblies. The canister may be subject to service-induced degradation when it is exposed to aggressive atmospheric environments during a possibly long-term storage period if the permanent repository is yet to be identified and readied. Because heat treatment for stress relief is not required for the construction of an MPC, stress corrosion cracking may be initiated on the canister surface in the welds or in the heat affected zone. An acceptance criteria methodology is being developed for flaw disposition should the crack-like defects be detected by periodic Inservice Inspection. The first-order instability flaw sizes has been determined with bounding flaw configurations, that is, through-wall axial or circumferential cracks, and part-through-wall long axial flaw or 360° circumferential crack. The procedure recommended by the American Petroleum Institute (API) 579 Fitness-for-Service code (Second Edition) is used to estimate the instability crack length or depth by implementing the failure assessment diagram (FAD) methodology. The welding residual stresses are mostly unknown and are therefore estimated with the API 579 procedure. It is demonstrated in this paper that the residual stress has significant impact on the instability length or depth of the crack. The findings will limit the applicability of the flaw tolerance obtained from limit load approach where residual stress is ignored and only ligament yielding is considered.


1997 ◽  
Vol 53 (6) ◽  
pp. 861-869 ◽  
Author(s):  
C. D. Ling ◽  
J. G. Thompson ◽  
S. Schmid ◽  
D. J. Cookson ◽  
R. L. Withers

The structures of the layered intergrowth phases SbIIISb^{\rm V}_xAl-xTiO6 (x \simeq 0, A = Ta, Nb) have been refined by the Rietveld method, using X-ray diffraction data obtained using a synchrotron source. The starting models for these structures were derived from those of Sb^{\rm III}_3Sb^{\rm V}_xA 3−xTiO14 (x = 1.26, A = Ta and x = 0.89, A = Nb), previously solved by single-crystal X-ray diffraction. There were no significant differences between the derived models and the final structures, validating the approach used to obtain the models and confirming that the n = 1 and n = 3 members of the family, Sb^{\rm III}_nSb^{\rm V}_xA n−xTiO4n+2 are part of a structurally homologous series.


Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1415 ◽  
Author(s):  
Guillaume Geandier ◽  
Lilian Vautrot ◽  
Benoît Denand ◽  
Sabine Denis

In situ high-energy X-ray diffraction using a synchrotron source performed on a steel metal matrix composite reinforced by TiC allows the evolutions of internal stresses during cooling to be followed thanks to the development of a new original experimental device (a transportable radiation furnace with controlled rotation of the specimen). Using the device on a high-energy beamline during in situ thermal treatment, we were able to extract the evolution of the stress tensor components in all phases: austenite, TiC, and even during the martensitic phase transformation of the matrix.


2018 ◽  
Vol 20 (9) ◽  
pp. 6629-6637 ◽  
Author(s):  
Alae El Haitami ◽  
Michel Goldmann ◽  
Philippe Fontaine ◽  
Marie-Claude Fauré ◽  
Sophie Cantin

A first-order phase transition with a peculiar feature is evidenced by means of in situ grazing incidence X-ray diffraction in the 2D organic phase-mediated nucleation of an inorganic layer.


Sign in / Sign up

Export Citation Format

Share Document