M.P. Dokhov, E. Kh. Sherieva, M.N. Kokoeva.
ABSTRACT
In the article, using experimental data known from the literature on wetting angles of refractory metals with liquid zinc, calculations of interfacial energies in these systems are made.
Due to the fact that there is no direct method for measuring the interfacial energy at the solid – melt interface of another metal, the calculation of this value becomes an urgent task.
Since the calculations of interfacial energies at the interface of solid metals with liquid zinc are carried out using the values of surface energies of solid metals measured by the non-contact method, i.e. in the absence of contact with the liquid metal, it is not possible to account for the influence of the liquid phase on the surface energy of the solid metal. However, if we keep in mind that zinc does not form solutions and compounds with these metals, then the influence of liquid zinc on the surface energies of solid metals can probably be ignored.
If the specific free surface energy is greater than the interfacial energy at the solid – melt interface, then the equilibrium edge angle is sharp, otherwise, i.e. at, the wetting angle is blunt.
At a wetting angle greater than ninety degrees, the greater the adhesion of the liquid to the solid metal, the closer the wetting angle is to the right angle, but its ratio to the surface energy of the melt remains less than one. A further increase in the absolute value of the edge angle reduces the adhesion to zero at 180°. Under equilibrium conditions in any systems, the wetting angle does not appear to reach 180°. The results of calculations of the interphase energies of the studied systems show the fundamental applicability of the young equation for calculating the interphase energy at the solid-liquid (melt) interface in systems where chemical reactions do not occur, that is, under equilibrium conditions. These results can be used in the selection of metal melts when soldering products made of refractory metals.
KEY WORDS:
interfacial energy, surface energy, solid metal, liquid metal, contact angle, boundary angle.
DOI: 10.31857/S0235010620060031