Wetting of T[lc]iN by liquid copper

Abstract

In the framework of an extensive study aimed at evaluating the wettability and the surface characteristics of different metal-ceramic systems, the behavior of TiN in contact with liquid copper was tested. TiN(x) specimens were made by annealing Ti metal sheets (3 mm thick) in a cold-wall autoclave at about 9 bar N2 and at 1900 K for times as long as 200 hours. Through this process all the titanium is converted into compact titanium nitride which allows meaningful wettability experiments, with an accuracy difficult to reach with sintered bodies. The stoichiometry has been determined by X-ray diffraction, XPS and RAMAN spectroscopy. The wetting experiments have been performed by the sessile drop technique in a ad-hoc furnace under pure fluxing He-5 percent H2 mixtures. In each run, both contact angles and liquid surface tension were measured by using a specially developed procedure (ASTRA, copyrighted) allowing these data to be recorded in real time. Results are presented on the wetting characteristics and of the interfacial reactions as a function of time.