Surface Tension and Viscosity of Industrial Ti-Alloys Measured by the Oscillating Drop Method on Board Parabolic Flights

The surface tension and the viscosity of Ti6Al4V, Ti6424, and of a gamma-TiAl alloy were measured by the oscillating drop method with an electromagnetic levitation device on board a series of parabolic flights. Parabolic flights offer twenty seconds of reduced gravity during which a specimen can be positioned under nearly force-free conditions and measurements in the liquid phase can be performed. The surface tension of Ti6Al4V and Ti6424 at the liquidus temperature has been obtained as sigma(T-1) = 1,52 Nm(-1) and 1.53 Nm(-1), respectively, while for gamma-TiAl a value sigma(T-1) = 1.28 Nm(-1) was obtained. The viscosity of Ti6Al4V and Ti6424 at the liquidus temperature was obtained as eta(T-1) = 4.76 mPa s and 4.82 mPa s. The viscosity of the gamma-TiAl at T-1 was obtained as eta(T-1) = 9.2 mPa s. The experimental method and data evaluation from the parabolic flights are described.