Imperial College London

Professor WE (Bill) Lee FREng

Faculty of EngineeringInstitute for Security Science & Technology

Co-Director of Institute for Security Science and Technology
 
 
 
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Contact

 

+44 (0)20 7594 6733w.e.lee Website

 
 
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Assistant

 

Ms Denise McGurk +44 (0)20 7594 8864

 
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Location

 

Central LibrarySouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Gasparrini:2017:10.1016/j.jnucmat.2017.07.016,
author = {Gasparrini, C and Podor, R and Horlait, D and Rushton, MJD and Fiquet, O and Lee, WE},
doi = {10.1016/j.jnucmat.2017.07.016},
journal = {JOURNAL OF NUCLEAR MATERIALS},
pages = {127--137},
title = {Oxidation of UC: An in situ high temperature environmental scanning electron microscopy study},
url = {http://dx.doi.org/10.1016/j.jnucmat.2017.07.016},
volume = {494},
year = {2017}
}

RIS format (EndNote, RefMan)

TY  - JOUR
AB - In situ HT-ESEM oxidation of sintered UC fragments revealed the morphological changes occurring during the transformation between UC to UO2 and UO2 to U3O8 at 723–848 K and in an atmosphere of 10–100 Pa O2. Two main oxidation pathways were revealed. Oxidation at 723 K in atmospheres ≤25 Pa O2 showed the transformation from UC to UO2+x, as confirmed by post mortem HRTEM analysis. This oxidation pathway was comprised of three steps: (i) an induction period, where only surface UC particles oxidised, (ii) a sample area expansion accompanied by crack formation and propagation, (iii) a stabilisation of the total crack length inferring that crack propagation had stopped. Samples oxidised under 50 Pa O2 at 723 K and at 773–848 K for 10–100 Pa O2 showed an “explosive” oxidation pathway: (i) sample area expansion occurred as soon as oxygen was inserted into the chamber and crack propagation and crack length followed an exponential law; (ii) cracks propagated as a network and the oxide layer fragmented, (iii) an “explosion” occurred causing a popcorn-like transformation, typical for oxidation from UO2 to U3O8. HRTEM characterisation revealed U3O8 preferentially grow in the [001] direction. The explosive growth, triggered by ignition of UC, proceeded as a self-propagating high-temperature synthesis reaction, with a propagation speed of 150–500 ± 50 μm/s.
AU - Gasparrini,C
AU - Podor,R
AU - Horlait,D
AU - Rushton,MJD
AU - Fiquet,O
AU - Lee,WE
DO - 10.1016/j.jnucmat.2017.07.016
EP - 137
PY - 2017///
SN - 0022-3115
SP - 127
TI - Oxidation of UC: An in situ high temperature environmental scanning electron microscopy study
T2 - JOURNAL OF NUCLEAR MATERIALS
UR - http://dx.doi.org/10.1016/j.jnucmat.2017.07.016
UR - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000410561200016&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
UR - http://hdl.handle.net/10044/1/54287
VL - 494
ER -