Determination of solution enthalpy of zirconium in liquid aluminum
Résumé
The work presented in this paper is the continuation of our earlier publication (Barrachin et al., 2019) where the literature data on the calorimetric measurements of the zirconium dissolution in liquid aluminum at temperatures around 1000 K were carefully analyzed. In this previous study, we showed that these different data were erroneously interpreted by their authors in terms of dissolution enthalpies. In our interpretation, the measured thermal effects rather resulted from the initial complete transformation of Zr into Al3Zr, due to the quick diffusion of aluminum towards the zirconium sample core. In this scenario, the subsequent dissolution of the aluminide particle in the melt, which is very slow at this temperature, was likely to remain undetected in the calorimetric experiments. To overcome these difficulties, the partial drop-solution enthalpy of zirconium at infinite dilution is indirectly derived from Al3Zr dissolution in liquid aluminum at 1173 K. It is found to be = −130 ± 9 kJ.mol−1. The corresponding partial mixing enthalpy of Zr at the liquid state is = −175 ± 10 kJ.mol−1. This value is consistent with the results obtained by various authors having performed calorimetric experiments at temperatures higher than 1700 K. It can hence be concluded that the zirconium partial mixing enthalpy at infinite dilution does not depend on temperature between 1173 K and 2045 K.
Domaines
MatériauxOrigine | Fichiers produits par l'(les) auteur(s) |
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