Abstract
Fission fragment energy deposition in nuclear fuel has been experimentally observed to influence the diffusion of uranium. This deposition is initially dominated by inelastic interactions with the electronic structure. Subsequently, the energy is transported to the lattice through electron-phonon (e-p) coupling resulting in a thermal spike and an associated pressure gradient, which are presumed to contribute to diffusion enhancement. Molecular dynamics (MD) simulations were performed to investigate uranium diffusion enhancement in UO2 while varying the e-p coupling. The model was composed of 10x60x60 unit cells and used a Buckingham potential. A two-temperature model captured energy deposition in the electronic subsystem and its transfer to a disordered region of the lattice. Experimentally, the fission enhanced diffusion coefficient of uranium in UO2 is observed to be proportional to fission rate density with a proportionality constant between 10−31 −10−29 cm5. The MD predicted proportionality constant showed reasonable agreement with experiment and decreased as the e-p coupling was weakened.
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
Preview
Unable to display preview. Download preview PDF.
References
Hj. Matzke, “Radiation Effects in Nuclear Fuels,” Radiation Effects in Solids, ed. Kurt E. Sickafus, Eugene A. Kotomin, and Blas P. Uberuaga ed. (Berlin, Germany: Springer 2007), 401–420.
Hj. Matzke, “Radiation damage in crystalline insulators, oxides and ceramic nuclear fuels,” Radiation Effects, 64 (1–4) (1982), 3–33.
A. Höh, and Hj. Matzke, “Fission-enhanced self-diffusion of uranium in UO2 and UC,” J. Nucl. Mat, 48 (2) (1973), 157–164.
Hj. Matzke, “Radiation enhanced diffusion in UO2 and (U,Pu)O2,” Radiation Effects, 75 (1–4) (1983), 317–325.
J.F. Ziegler, M.D. Ziegler, and J. P. Biersack, “SRIM: The stopping and range of ions in matter (2010),” Nucl. Instrum. Meth. Rhys. Res. B, Beam Interact. Mater. At., 268 (11–12) (2010), 1818–1823.
D.K. Avasthi, and G.K. Mehta, Swift Heavy Ions for Materials Engineering and Nanostructuring (New Delhi, India: Capital Publishing Company, Springer 2011), 47–64.
J.M. Harp, “Examination of Noble Fission Gas Diffusion in Uranium Dioxide Using Atomistic Simulation” (Ph.D. thesis, North Carolina State University, 2010), 39–41, 67–95.
S.J. Plimpton, “Fast parallel algorithms for short-range molecular dynamics”, J. Comp. Rhys 117 (1995) 1–19. http://lammps.sandia.gov.
S.J. Plimpton, R. Pollock, M. Stevens, “Particle-mesh ewald and rRESPA for parallel molecular dynamics simulations,” in Proc. of the Eighth S1AM Conference on Parallel Processingfor Scientific Computing, Minneapolis, MN (1997). http://lammps.sandia.gov.
I.M. Eifshitz, M.I. Kaganov, and E.V. Earatanov, “On the theory of radiation-induced changes in metals,” J. Nucl. Energy A, 12 (1960), 69–78.
M. Eoulemonde, E. Paumier, and C. Dufour, “Ehermal spike model in the electronic stopping power regime,” Radiat. Eff. Defects Solids, 126 (1–4) (1993), 201–206.
M. Eoulemonde et al, “Eransient thermal process in heavy ion irradiation of crystalline inorganic insulators,” Nucl. Instr. andMeth. in Rhys. Res. B, 166–167 (2000), 903–912.
M. R. P. Waligorski, R. N. Hamm, and R. Katz, “The radial distribution of dose around the path of a heavy ion in liquid water,” Nucl. Tracks Meas. 11 (6) (1986), 309–319.
M. Toulemonde et al, “Experimental phenomena and thermal spike model description of ion tracks in amporphisable inorganic insulators,” Matematisk-Fysiske Meddelelser 52 (2006), 263–292.
E. Wiss et al, “Radiation damage in UO2 by swift heavy ions,” Nucl. Instr. and Meth. in Rhys. Res. B, 122 (3) (1997), 583–588.
A. Caro, and M. Victoria, “Ion-electron interaction in molecular dynamics cascades,” Phys. Rev. B, 40 (5) (1989), 2287–2291.
D. M. Duffy, A.M. Rutherford, “Including the effects of electronic stopping and electron-ion interactions in radiation damage simulations,” J. Phys. Condens. Matter, 19 (1) (2007).
Author information
Authors and Affiliations
Editor information
Rights and permissions
Copyright information
© 2014 TMS (The Minerals, Metals & Materials Society)
About this paper
Cite this paper
Wormald, J.L., Hawari, A.I. (2014). Exploring Fission Enhanced Diffusion of Uranium in Uranium Dioxide Using Classical Molecular Dynamics Simulations. In: TMS 2014: 143rd Annual Meeting & Exhibition. Springer, Cham. https://doi.org/10.1007/978-3-319-48237-8_21
Download citation
DOI: https://doi.org/10.1007/978-3-319-48237-8_21
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-48593-5
Online ISBN: 978-3-319-48237-8
eBook Packages: Chemistry and Materials ScienceChemistry and Material Science (R0)