WETTING OF TITANIUM-TANTALUM CARBONITRIDE SOLID-SOLUTION BY IRON SUBGROUP METALS

The sessile drop method has been used to determine the limiting wettin g angles for titanium-tantalum carbonitride by metals of the iron subg roup in nitrogen and vacuum. The wetting angle is reduced when one pas ses from iron to cobalt and nickel, which corresponds to the character istic variation in theta in the wetting by the iron subgroup metals of pure refractory-metal carbides. X-ray microspectralanalysis indicates the contact interactions in these systems. The limiting wetting angle for titanium-tantalum carbonitride is reduced by comparison with pure titanium carbide on account of tantalum diffusing into the metal in c ontact with it, as a result of donor-acceptor interaction activation. It is suggested that the Ti0.75Ta0.25C0.5N0.5 - Me(VIII) sections are quasibinary eutectic ones.