Thermodynamic modelling of the C–U and B–U binary systems

Laser melting of uranium carbides

“…This behaviour suggests that probably higher uranium carbides do not melt congruently like UC, but rather through a solidus/liquidus scheme, which can lead to segregation phenomena if the cooling rate is too high, and hence to less well defined thermograms and more complex surface morphologies, as observed using the Reflected Light Signal and SEM. According to the assessed shape of the phase diagram, by Chevalier and Fischer [11] and Guéneau et al [4], a eutectic point is certainly present between UC and UC 2 . This point is probably located in the vicinity of the composition UC 1.5 , for which the best defined thermal arrests were observed, corresponding to the lowest average liquidus point (2684 K), and a small liquidus-solidus gap (approximately 23 K).…”

Electronic structure of UCx films prepared by sputter co-deposition

“…We used mainly photoemission but also X-ray diffraction (XRD) to characterize the compounds. One question was whether all the three uranium carbide compounds (UC, U 2 C 3 and UC 2 ) [5] could be obtained by our method.…”

Progress in understanding fission-product behaviour in coated uranium-dioxide fuel particles

“…The CALPHAD models of the two border sub-systems, U-C and U-O, of the U-C-O phase diagram, published in [15,16], are parts of the MEPHISTA modelling. In particular, the U-O model satisfactorily reproduces the experimental database for oxygen potential in UO 2+x that governs the free oxygen over the hyperstoichiometric fuel for the carbonic gas formation.…”