FULLEREN-LIKE STRUCTURE OF NANOCRYSTALLINE MoS2 TRIBOLOGICAL COATINGS PREPARED WITH COMPOSITION- MODULATED INTERFACES

Nanocomposite thin film coatings of MoS2-added CrN/TiAlN tribological multilayers were prepared by reactive co-sputtering of Ti/Al 50/50 at.%, pure chromium and MoS2 targets of the independently d.c. driven unbalanced magnetrons. Nano-scaled tri-layer system with periodic thickness in a range of 4-10 nm of CrN, TiAlN and MoS2 compound layer with a broad interface, in which the composition is continuously varying, was developed. The 4-5 μm thick coatings were deposited on high-speed steel substrates for tribological measurements. Structure characterization of the as-deposited coatings was performed by cross sectional transmission electron microscopy (XTEM) analysis. The crystallinity of the CrN and TiAlN sub-layers in the nano-scale multilayered system decreases with increasing thickness of the MoS2 sub-layer. It has been found that the structural properties and hardness of the films were correlated with the multiple-target design and MoS2 nanolayer thickness.