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Title: Molecular Dynamics Simulation of Fission Fragment Damage in Nuclear Fuel and Surrogate Material

Abstract

ABSTRACT We have performed classical molecular dynamics simulations of swift heavy ion damage, typical of fission fragments, in nuclear fuel (UO 2) for energy deposition per unit length of 3.9 keV/nm. We did not observe amorphization. The damage mainly consisted of isolated point defects. Only about 1% of the displacements occur on the uranium sublattice. Oxygen Frenkel pairs are an order of magnitude more numerous than uranium Frenkel pairs in the primary damage state. In contrast, previous results show that the ratio of Frenkel pairs on the two sublattices is close to the stoichiometric ratio in ceria. These differences in the primary damage state may lead to differences in radiation response of UO 2and CeO 2.

Authors:
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1361956
Report Number(s):
PNNL-SA-123157
Journal ID: ISSN 2059-8521
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: MRS Advances; Journal Volume: 2; Journal Issue: 21-22
Country of Publication:
United States
Language:
English
Subject:
Molecular dynamics; radiation damage in materials; Nuclear Fuel Performance

Citation Formats

Devanathan, Ram. Molecular Dynamics Simulation of Fission Fragment Damage in Nuclear Fuel and Surrogate Material. United States: N. p., 2017. Web. doi:10.1557/adv.2017.9.
Devanathan, Ram. Molecular Dynamics Simulation of Fission Fragment Damage in Nuclear Fuel and Surrogate Material. United States. doi:10.1557/adv.2017.9.
Devanathan, Ram. Sun . "Molecular Dynamics Simulation of Fission Fragment Damage in Nuclear Fuel and Surrogate Material". United States. doi:10.1557/adv.2017.9.
@article{osti_1361956,
title = {Molecular Dynamics Simulation of Fission Fragment Damage in Nuclear Fuel and Surrogate Material},
author = {Devanathan, Ram},
abstractNote = {ABSTRACT We have performed classical molecular dynamics simulations of swift heavy ion damage, typical of fission fragments, in nuclear fuel (UO2) for energy deposition per unit length of 3.9 keV/nm. We did not observe amorphization. The damage mainly consisted of isolated point defects. Only about 1% of the displacements occur on the uranium sublattice. Oxygen Frenkel pairs are an order of magnitude more numerous than uranium Frenkel pairs in the primary damage state. In contrast, previous results show that the ratio of Frenkel pairs on the two sublattices is close to the stoichiometric ratio in ceria. These differences in the primary damage state may lead to differences in radiation response of UO2and CeO2.},
doi = {10.1557/adv.2017.9},
journal = {MRS Advances},
number = 21-22,
volume = 2,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2017},
month = {Sun Jan 01 00:00:00 EST 2017}
}
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