On the present state of investigation of thermodynamic properties of solid and liquid UO2+x

Atomistic modeling of the vibrational and thermodynamic properties of uranium dioxide, UO2

“…It is the usual fuel used for pressurized heavy water reactors. Knowledge of the thermodynamic and transport properties of nuclear fuel at high temperatures is of great interest [1][2][3][4][5][6][7]. A clear understanding of its thermophysical [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] properties is of utmost need for its various applications.…”

“…Uranium atoms form a face centered cubic network, all tetrahedral sites of which are occupied by oxygen atoms. This compound shows a type-II superionic transition attaining high levels of ionic conductivity following a gradual and continuous disordering process within the same phase [1,2,5]. Several theoretical and experimental works have been reported on numerous fast-ion conductors like Li 2 O, CaF 2 , BaF 2 , PbF 2 , SrCl 2 , CuI, etc., [28].…”

New modelling of the U–O–Zr phase diagram in the hyper-stoichiometric region and consequences for the fuel rod liquefaction in oxidising conditions

“…To our opinion, different convincing arguments detailed in [22,26] are clearly in favor of the laser flash technique by comparison with the facility used by Latta and Fryxell [21]. They are the control of the composition of the sample during heating since there is no evaporation of oxygen due to the high imposed isostatic pressure, the absence of the crucible suppressing a possible interaction between the latter and the sample and finally the determination of the solidus and liquidus temperatures by different independent means.…”

Over forty years of ‘Thermodynamics of Nuclear Materials’

“…The development of this EOS, requires development of models for the liquid and extrapolations of experimental data to temperatures above 10000 K. There is little experimental data above the melting point of UO 2 at 3120 K. There have been, however, some very significant measurements of the specific heat of this compound up to 8000 K [96,97]; these data are shown in Fig. 16 and also measurements on, for example, the melting temperatures of UO 2 + x using a container-less laser heating together with fast spectral pyrometry [98].…”