Structure and properties of nanoscale MoN/CrN multilayered coatings

Multilayered nanostructured coatings consisting of MoN and CrN alternating layers have been considered. The coatings obtained by arc-vacuum deposition in 3 series with different bias potential. The thickness of bilayers has been varied from micro (1.73 μm) to nanosizes (36÷41 nm). Parameters of deposition have been changed, such as bias potential from −20 V to −300 V and chamber pressure from 7×10⁻⁴ to 3×10⁻³ Torr. An element and structural analysis performed with XRD, SEM (with EDS), RBS, SIMS methods has shown well properties of obtained coatings, with clearly allocated layers of CrN and MoN. It is found formation of mononitride CrN and Mo2N with cubic lattice NaCl-type. Decreasing of bilayers thickness to (36÷41) nm has provided high hardness (38÷42) GPa and wear resistance. Remarkable that increasing of chamber pressure leads to increase of wear resistance.