Corrosion behavior of Ti2N thin films in various corrosive environments N. S.

Hard ceramic coatings play an important role in tribological applications, a few such as titanium nitride coatings also has decorative applications. In both the applications they are exposed to corrosive environments. In present investigation single component Ti-N thin films of varying thickness (1.5^, 2.0^, 2.5^, 3.0^ and 4.0^) were deposited on 316 stainless steel using Ti (99.95%) pure metal target by cathode arc evaporation PVD technique. Scanning electron microscopy (SEM) and XRD were employed to analyze microstructures and phases present in the coating. XRD results indicated presence of substoichiometric Ti2N. Corrosion resistance of Ti2N films was determined using potentiodynamic tests in most common industrial environments 3.5% NaCl and 1 N H2SO4. The results indicate that corrosion resistance in both the environments is higher for coating of 3.0^ and 4.0^ thickness compared to the less thick 1.5^ and 2.0^.