The Wetting of an Alumina Substrate by Liquid Silver

Abstract The wetting of the Al2O3 substrate by liquid silver was investigated by means of the sessile-drop technique in an atmosphere of argon. An empirical relation was established between the contact angle and the temperature or surface tension of the liquid drop by the use of the diameter and the height of the sessile drop. The contact angle was constant as the time increased while it decreased linearly with the increase in the temperature. The variation in the contact angle with the temperature is correlated with the surface tension of the sessile drop. The critical surface tension (γc) of Al2O3 is 361 dyn cm−1, while the surface tension of liquid silver at 0 K is 790 dyn cm−1.