Surface tension of molten nickel-chromium alloy

摘要

The surface tension of molten Ni and Ni-Cr (5 and 10 mass fraction) alloys was measured at temperatures of 1773 K ~ 1873 K using an improved sessile drop method with an alumina substrate in an Ar+3%H2 atmosphere. The surface tension of molten Ni and Ni-Cr (5 and 10 mass fraction) alloys was found to decrease with increasing temperature. On the basis of the experimental data obtained, the surface tension was also theoretically deduced both as functions of concentration and temperature using a model of Butler's equation. The results agreed well with a model for the surface tension. The difference between the experimental data and deduced data may be caused by the measurement error, the assumptions for a surface such as monolayer atom, and the differences in the energy of the Gibbs' free energy of the surface. Chromium was found to segregate on the surface of molten alloys.