Experimental kinetic study of oxidation of uranium monocarbide powders under controlled oxygen partial pressures below 230 °c Article

Berthinier, C, Rado, C, Dugne, O et al. (2013). Experimental kinetic study of oxidation of uranium monocarbide powders under controlled oxygen partial pressures below 230 °c . JOURNAL OF NUCLEAR MATERIALS, 432(1-3), 505-519. 10.1016/j.jnucmat.2012.08.002

cited authors

  • Berthinier, C; Rado, C; Dugne, O; Cabie, M; Chatillon, C; Boichot, R; Blanquet, E

authors

abstract

  • Uranium monocarbide (UC) powders are known to be easily oxidised by gas mixtures containing oxygen. In this study, the oxidation of UC micron powders was followed by isothermal thermogravimetry at temperatures ranging from 100 °C to 230 °C in two different gas mixtures: synthetic air and 97%N 2 + 3%O2. X-ray diffraction tests conducted on powders after their oxidation showed that small crystallites of UO2 oxide are formed. Furthermore, an analysis of mass gain showed that the carbon initially linked with the uranium is not oxidised but retained in oxide layers. Additionally, this kinetic study revealed that the rate-limiting step mechanism governing the oxidation of UC powders is a diffusive process that follows the Arrhenius law regarding temperature. Finally, it was discovered that cracks occur in grains once a given fractional conversion has been reached, inducing a major increase in the volume of grains. © 2012 Elsevier B.V. All rights reserved.

publication date

  • January 1, 2013

published in

Digital Object Identifier (DOI)

start page

  • 505

end page

  • 519

volume

  • 432

issue

  • 1-3