Hard multilayer coatings are technologically promising materials for reducing wear of tribological parts. Multilayer coatings with a systematic alternation of the pair [(TiCx/Ti/C)÷(a-C)] were deposited on stainless and tool steel by the PVD technique. Hardness (H), elasticity modulus (E) and critical cracking load (Pcr) were determined by the nanoindentation method. Nanofrictional wear test was conducted under multipass sliding of a diamond indenter (Ø 50 nm) under constant load. The specific coefficient of nanofrictional wear of [(TiCx/Ti/C)÷(a-C)]nwith different composition of titanium-containing layers was determined. The nanofrictional wear rate of [(TiCx/Ti/C)÷a-C]ndepends on the elastic and plastic characteristics of multilayer coating as a whole. Coatings having H3/E2> 0.12 and Pcr> 58 mN demonstrate low wear rate.

A focus point in this work was the research of the influence of deposition condition on properties of CrAlC films. CrAlC films were deposited by arc sputtering technique using arc sputtering of Cr-Al target and pulse arc sputtering of graphite target at different frequency. The multilayer [(CrAlC)+(a-C)]ncoatings were also obtained and investigated. Multilayer [(CrAlC)+(a-C)]nwere deposited with a systematic alternation of the pair [(CrAlC)+(a-C)], where a-C is the amorphous carbon layer. The structure, mechanical properties and fracture toughness of CrAlC films depend on pulse frequencies of the graphite sputtering. With increasing pulse frequency, the film structure changes from uniformly amorphous to amorphous with nanograins, the hardness of the films increases, the critical load of crack formation and film peeling tend to decrease. It is shown that a decrease in the thickness of the layers in [(CrAlC)+(a-C)]nleads to an increase in the crack resistance.