The surface tensions of indium and cadmium

The surface tensions of 99.9999 pct In and Cd have been measured by the sessile drop method. The surface tension/temperature behavior of liquid indium is nonlinear and within a certainty of 99.5 pct, can be represented by the following quadratic equation:γ _In = 568.0 − 0.04t − 7.08 × 10⁻⁵ t ² ± 5 dyne per cm At its melting point, the surface tension of liquid indium is 560 ± 5 dyne per cm. The slope of the temperature coefficient of the surface tension of liquid cadmium is strongly positive at the melting point, becomes zero about 100°C above the melting temperature (at which point the surface tension is a maximum), and is negative at higher temperatures. At the melting point, the surface tension of cadmium is 590 ± 5 dyne per cm. The surface tension of cadmium is not as readily affected by nonequilibrium thermal conditions as is the surface tension of zinc. The form of the surface tension/temperature curve of indium and cadmium together with similar data for Zn, Cu, Pb, and Sn support a theoretical scheme which generalizes liquid metal surface tension behavior and which, on the basis of calculations, lists liquid metals according to their propensity for surface ordering.