Imperial College London
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ProfessorRobinGrimes

Faculty of Engineering, Department of Materials

BCH Steele Chair in Energy Materials
 
 
 
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Contact

 

+44 (0)20 7594 6730r.grimes

 
 
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Location

 

B303cBessemer BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Kuganathan:2018:10.1016/j.jnucmat.2018.05.006,
author = {Kuganathan, N and Ghosh, P and Arya, A and Grimes, R},
doi = {10.1016/j.jnucmat.2018.05.006},
journal = {Journal of Nuclear Materials},
pages = {288--296},
title = {Helium trapping and clustering in ThO2},
url = {http://dx.doi.org/10.1016/j.jnucmat.2018.05.006},
volume = {507},
year = {2018}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Helium, generated in nuclear fuel, accomodates into bubbles and degrades mechanical stability. Atomic scale simulations were used to study the interaction of He atoms with point defects and defect clusters. The incorporation of a single He atom was unfavourable at an octahedral interstitial site by 0.92eV compared to the gas phase reference state, by 0.68eVat an oxygen vacancy and by 0.32eVat a Th vacancy. The decreasing values reflect the greater space available for the inert He atom. Defect clusters consisting of multiple oxygen and Th vacancies provide more space. Thus, incorporation at a di-vacancy required 0.31eV, at a neutral tri-vacancy (NTV) 0.25eV and at a tetra-vacancy 0.01eV. Clusters formed of two and three NTVs exhibited no energy penalty for the incorporation of multiple He atoms. Relative to incorporation at an interstitial site, clusters offer space for multiple He and may therefore be effective traps to form proto-bubbles. A relationship was generated that describes the incorporation energy of the xth He atom, Ex (n, m), into a cluster consisting of n thorium vacancies and m oxygen vacancies. Solution energies for He, where equilibrium with the solution site is taken into account, were also determined.
AU  - Kuganathan,N
AU  - Ghosh,P
AU  - Arya,A
AU  - Grimes,R
DO  - 10.1016/j.jnucmat.2018.05.006
EP  - 296
PY  - 2018///
SN  - 0022-3115
SP  - 288
TI  - Helium trapping and clustering in ThO2
T2  - Journal of Nuclear Materials
UR  - http://dx.doi.org/10.1016/j.jnucmat.2018.05.006
UR  - http://hdl.handle.net/10044/1/69295
VL  - 507
ER  -
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