The Surface Tension and Density of Molten Sc2 O3 , La2 O3 , Y2 O3 , Al2 O3 , and MgO Measured via a Pendant Droplet Method

A thermal imaging furnace (TIF) was used to study the physical properties of molten Sc2O3 , La2O3, Y2O3, Al2O3 and MgO via a containerless method. The density and surface tension of molten droplets of Sc2O3 , La2O3, Y2O3, Al2O3, and MgO suspended from their own solid were measured in situ using live video under a range of oxygen partial pressures (1→10−6 atm O2). To the best knowledge of the authors, this is the first time the surface tension and density of molten MgO and Sc2O3 have been reported. A relationship between molten oxide surface tension and the enthalpy of vaporization is proposed, and a comparison is drawn between the oxide properties and similar relationships previously established for liquid metals.