Abstract
In order to discuss the temperature dependence of surface tension of liquid pure metals, the surface tension of Cu, Ag, Au, Sn and Pb in the liquid state has carefully been measured by the sessile drop method in an atmosphere of prepurified hydrogen or argon, with a partial oxygen pressure of about 10−20 atm, over the temperature range between the melting points and 1450°C. The surface tension of their metals decreased linearly with increasing temperature over the entire temperature range irrespective of the kinds of atmospheric gas. Furthermore, based on the data obtained in the present experiment and a previously established theory of surface tension of liquid pure metals at temperatures close to their melting points, a consideration was made to account for the temperature dependence of surface tension of liquid pure metals from the phenomenological standpoint and an simple equation for the temperature change of surface tension of liquid pure metals was derived in terms of the atomic volume (or density) as a parameter: γ\simeq\frac12 ·\fracπ^2β^2C^2T_mN \frac{(1+α)V_m^1/3-V_T^1/3}^2V_T^4/3
It was shown that the values of surface tension calculated by the above equation were in good agreement with a series of experimental values obtained in the present work and by other investigators.
