Non-contact measurements of surface tension and viscosity of niobium, zirconium, and titanium using an electrostatic levitation furnace

The surface tension and viscosity of liquid niobium, zirconium, and titanium have been determined by the oscillation drop technique using a vacuum electrostatic levitation furnace. These properties are reported over wide temperature ranges, covering both superheated and undercooled liquid. For niobium, the surface tension can be expressed as sigma(T) = 1.937x10(3) - 0.199(T-T-m) (mN.m(-1)) with T-m = 2742 K and the viscosity as eta(T) = 4.50-5.62x10(-3)(T-T-m) (mPa.s), over the 2320 to 2915 K temperature range. Similarly, over the 1800 to 2400 K temperature range, the surface tension of zirconium is represented as sigma(T) = 1.500x10(3)-0.111(T-T-m) (mN.m(-1)) and the viscosity as eta(T) = 4.74-4.97 x10(-3)(T-T-m) (mPa.s) where T-m=2128 K. For titanium (T-m=1943 K), these properties can be expressed, respectively, as sigma(T)=1.557x10(3)-0.156(T-T-m) (mN.m(-1)) and eta(T) = 4.42-6.67x10(-3)(T-T-m) (mPa.s) over the temperature range of 1750 to 2050 K.