Development of an oscillating cup viscometer for viscosity measurement of liquid metals at very high temperatures

Abstract

The dynamic viscosity of molten metals is measured over a wide temperature range up to 2100 K using an oscillating cup viscometer. In order to further reduce the measurement uncertainties, a particular attention is paid to thermal effects, temperature measurement, acquisition and analysis of the mechanical response of the oscillating pendulum. Experiments are first conducted at low temperature with standard liquids, covering a wide range of viscosities from 1 mPa.s to 500 mPa.s. These preliminary tests helped to assess the accuracy and reliability of the Shvidkovskiy approach used to calculate viscosity. Further experiments were then performed at very high temperature using an induction furnace. As a result, the dynamic viscosity has been successfully measured over the temperature range 506–2135 K for liquid tin, and 710–1770 K for liquid lead, providing unpublished data. Additionally, this was achieved while maintaining a relatively low uncertainty of about 2.5% despite the very high temperature reached here.