Noncontact surface tension measurement by drop rotation

Validity of the surface tension measurement technique that was proposed by Elleman et al. was experimentally verified. The technique was based on Brown and Scriven's work on the shape evolution of rotating drops. Molten tin and aluminum drops were levitated in high vacuum by the electrostatic levitator and rotated by applying a rotating magnetic field. This technique offers an alternative technique for those liquids where the drop oscillation technique cannot be used. As a demonstration, the technique was applied to a glass-forming alloy (Zr41.2Ti13.8Cu12.5Ni10.0Be22.5) and its surface tension was measured down to the lower temperature where the drop oscillation technique could not be applied due to its high viscosity.