Density and viscosity of liquid ternary Al-Cu-Ag alloys
Jürgen Brillo, Rob Brooks, Ivan Egry and Peter Quested
In this paper, we report on density and viscosity measurements of liquid Al-Cu-Ag alloys. The densities have been measured on electromagnetically levitated samples by a shadowgraph technique. The viscosities were obtained by means of an oscillating cup viscometer where a suspended crucible containing the liquid sample performs torsional oscillations damped by the viscosity of the liquid.
It was found that the density is a linear function of temperature for all investigated compositions. The concentration dependence of the molar volume exhibits a negative excess volume. The measured viscosities can be described as a function of temperature by an Arrhenius law, yielding an activation energy for the viscous flow. The viscosity and its apparent activation energy exhibit both a maximum at a certain composition.
Keywords: Al-Cu-Ag alloys, Density, Electromagnetic levitation, Excess volume, Viscosity, Oscillating cup viscometry.