Metal Nitride Coatings of (Cr/Mo)N and (Cr/Ti)N by Ion-Assisted Co-sputtering for Corrosion-Resistant Applications.

Due to their excellent hardness, transition metal nitrides have become a promising coating material for cutting tools and high-friction surfaces. The wear and corrosion protection offered by metal nitride hard coatings has paved the way for research on different combinations of metal nitrides. In this study, binary transition metal nitride coatings of CrMoN and CrTiN are deposited onto cutting tools and different substrates by co-sputtering of two metal targets simultaneously at an oblique angle by an ion-assisted DC magnetron sputtering process. The purpose of the deposition is to develop a uniform adhesive hard coating onto the specimens and to study their characteristics and performance. Both the hard adhesive coatings developed offer good surface morphologies which have been confirmed by AFM and FESEM, and their elemental composition is confirmed by XRD, XPS, and EDS characterizations. Hardness is measured by nanoindentation and also electrochemical studies for corrosion measurements are performed. In both the coatings, individual nitride phases have been formed in a mixed manner and have achieved a hardness value of about 13 GPa and the corrosion resistance of the coated specimen is found to be improved in comparison with the uncoated substrates. [ABSTRACT FROM AUTHOR]