Experimental measurement of surface tension of Cu-Ti liquid alloys
Stefano Amore, Jürgen Brillo and Ivan Egry
The electromagnetic levitation technique (EML) has been successfully employed in order to levitate Cu-Ti binary alloys. A digital CMOS-camera (400 fps) recorded image sequences of oscillating liquid sample and surface tension has been determined by oscillating drop method from the analysis of the frequency spectra. Measurements have been performed for samples covering the entire composition range and values have been obtained in a broad temperature range. Some samples have also been undercooled. The surface tension can be described as a linear function of temperature with negative slopes ranging between 2.3 × 10-4 [Nm-1K-1] for pure copper and 1.7 × 10-4 [Nm-1K-1] for pure Ti. Moreover the surface tension at T = 1423 K has been calculated and it shows a monotonically increasing behavior with the increasing of the Ti atomic concentration in the alloys.
Keywords: Cu-Ti liquid binary alloys; surface tension; electromagnetic levitation; liquid metal systems; surface properties; oscillating drop method