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arXiv · 2104.11521

Ab initio inspection of thermophysical experiments for zirconium near melting

Abstract

We present quantum molecular dynamics calculations of thermophysical properties of solid and liquid zirconium in the vicinity of melting. An overview of available experimental data is also presented. We focus on the analysis of thermal expansion, molar enthalpy, resistivity and normal spectral emissivity of solid and liquid Zr. Possible reasons of discrepancies between the first-principle simulations and experiments are discussed. Our calculations reveal a significant volume change on melting in agreement with electrostatic levitation experiments. Meanwhile, we confirm a low value of enthalpy of fusion obtained in some pulse-heating experiments. Electrical resistivity of solid and liquid Zr is systematically underestimated in our simulations, however the slope of resistivity temperature dependencies agrees with experiment. Our calculations predict almost constant normal spectral emissivity in liquid Zr.

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M. A. Paramonov, D. V. Minakov, V. B. Fokin, D. V. Knyazev, G. S. Demyanov, P. R. Levashov. 2021-04-23. Ab initio inspection of thermophysical experiments for zirconium near melting. https://doi.org/10.1063/5.0088504

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