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Dynamic Viscosity of the NaF-KF-NdF₃ Molten System.

ABSTRACT: The dynamic viscosity (η) of the molten system (NaF-KF)_eut-NdF₃ containing NdF₃ in an amount from 0 to 15 mol.% was studied by rotational viscometry using a high-temperature rheometer, FRS 1600. Viscosity measurements were carried out in the temperature range from liquidus to 1153 K. The measurement procedure was tested on the (LiF-NaF-KF)_eut melt. The choice of the parameter shear rate was carried out according to the viscosity and flow curves. Viscosity does not depend on shear rate, and therefore the investigated melts behave like Newtonian fluids, in the range of 9-19 s^-1. The experimentally obtained viscosity values for (NaF-KF)_eut-NdF₃ melts in a wide temperature range are described by an exponential equation. In the coordinates ln(η) = f(1/T), they are straight lines; however, their temperature coefficients are noticeably different, which indicates significant impacts of composition and temperature.

SUBMITTER: Rudenko A

PROVIDER: S-EPMC9324551 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Dynamic Viscosity of the NaF-KF-NdF3 Molten System.

Rudenko Alexei A Kataev Alexander A Tkacheva Olga O

Materials (Basel, Switzerland) 20220713 14

The dynamic viscosity (η) of the molten system (NaF-KF)eut-NdF3 containing NdF3 in an amount from 0 to 15 mol.% was studied by rotational viscometry using a high-temperature rheometer, FRS 1600. Viscosity measurements were carried out in the temperature range from liquidus to 1153 K. The measurement procedure was tested on the (LiF-NaF-KF)eut melt. The choice of the parameter shear rate was carried out according to the viscosity and flow curves. Viscos ...[more]

PMID: 35888350

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