Effect of carbon content on nanostructural, mechanical and electrochemical characteristics of self-organized nc-ZrCN/a-CNx nanocomposite films

The nanocomposite nc-ZrCN/a-CNx films with a carbon content varying from 34 to 61 at.% were deposited by filtered cathodic vacuum arc technique (FCVA) under different C2H2/N2 reactive gas flows. The effect of different carbon contents on compositional, nanostructural characteristics of nanocomposite nc-ZrCN/a-CNx films was investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscope (TEM), Raman scattering spectroscopy (Raman) and X-ray photoelectron spectroscopy (XPS). Results showed that nanocomposite nc-ZrCN/a-CNx films were composed of about 8 nm sized ZrCN nanocrystalline embedded in different amount of a-CNx amorphous matrix. Mechanical properties of nanocomposite nc-ZrCN/a-CNx films showed a significant dependency on thickness of a-CNx matrix. Nanocomposite nc-ZrCN/a-CNx film reached the highest hardness (41 GPa) and reduced modulus (320 GPa) when the thickness of a-CNx matrix was around 0.4 nm. Nanocomposite nc-ZrCN/a-CNx film at higher carbon content has lower friction coefficient (0.2) and better wear resistance. The nanocomposite films possess lower Icorr and higher Rp values than the single phase film.