Imperial College London
Alternate

Professor WE (Bill) Lee FREng

Faculty of Engineering, Institute for Security Science & Technology

Distinguished Research Fellow
 
 
 
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Contact

 

w.e.lee Website

 
 
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Assistant

 

Miss Eva Konstantara +44 (0)20 7594 8864

 
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Location

 

Abdus Salam LibrarySouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Humphry-Baker:2020:10.1016/j.ijrmhm.2020.105356,
author = {Humphry-Baker, SA and Ramanujam, P and Smith, GDW and Binner, J and Lee, WE},
doi = {10.1016/j.ijrmhm.2020.105356},
journal = {International Journal of Refractory Metals and Hard Materials},
title = {Ablation resistance of tungsten carbide cermets under extreme conditions},
url = {http://dx.doi.org/10.1016/j.ijrmhm.2020.105356},
volume = {93},
year = {2020}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - A cobalt-free tungsten carbide cermet (WC-FeNi) has been subjected to oxyacetylene flame tests to simulate extreme operating conditions such as a worst-case fusion reactor accident. In such an accident, air-ingress to the reactor may impinge on components operating at surface temperatures in excess of 1000°C, leading to tungsten oxide formation and its subsequent hazardous volatilisation. Here, the most challenging accident stage has been simulated, where the initial air-ingress could lead to extremely rapid air-flow rates. These conditions were simulated using an oxidising oxyacetylene flame. The separation between flame nozzle and sample was varied to permit peak surface temperatures of ~950–1400°C. When the peak temperature was below 1300°C, the cermet gained mass due to the dominance of oxide scale formation. Above 1300°C, the samples transitioned into a mass loss regime. The mass loss regime was dominated by ablation of the scale rather than its volatilisation, which was confirmed by performing a systematic thermogravimetric kinetic analysis. The result was unexpected as in other candidate shielding materials, e.g. metallic tungsten, volatilisation is considered the primary dispersion mechanism. The unusual behaviour of the cermet scale is explained by its relatively low melting point and by the lower volatility of its FeWO4 scale compared to tungsten's WO3 scale. The substantially lower volatility of the WC cermet scale compared to metallic W indicates it may have a superior accident tolerance.
AU  - Humphry-Baker,SA
AU  - Ramanujam,P
AU  - Smith,GDW
AU  - Binner,J
AU  - Lee,WE
DO  - 10.1016/j.ijrmhm.2020.105356
PY  - 2020///
SN  - 0263-4368
TI  - Ablation resistance of tungsten carbide cermets under extreme conditions
T2  - International Journal of Refractory Metals and Hard Materials
UR  - http://dx.doi.org/10.1016/j.ijrmhm.2020.105356
UR  - https://www.sciencedirect.com/science/article/pii/S0263436820302328?via%3Dihub
UR  - http://hdl.handle.net/10044/1/81982
VL  - 93
ER  -
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