CONTAINERLESS PROCESSING OF UNDERCOOLED MELTS - MEASUREMENTS OF SURFACE-TENSION AND VISCOSITY

Electromagnetic levitation is an elegant way of processing highly reactive liquid metals. It avoids contact with any container walls and thus protects the sample's surface from contamination. This is important not only for obtaining reliable surface tension data for the pure metals or alloys, but also for accessing the metastable. undercooled regime. With electromagnetic levitation, the undercooled state can be maintained for extended periods of time, allowing in situ diagnostics, i.e. non-contact measurements of thermophysical properties. The oscillating drop technique can be used to determine surface tension and viscosity as a function of temperature. The frequencies of the oscillations of liquid drops are related to the restoring force, the surface tension. while the damping of the oscillations is related to the viscosity.