Structure, Substructure, Hardness and Adhesion Strength of Multiperiod Composite Coatings MoN / CrN.

A comprehensive study of the influence of the thickness of the layers, Us and PN on the structural engineering to obtain high mechanical properties in multilayer composite MoN / CrN vacuum-arc coatings has been conducted by means of scanning electron microscopy with energy analysis, X-ray diffraction studies microindentation and scratch testing methods. It has been determined that in the studied P_N = (2- 30) x 10 ^-4 Torr, the content of nitrogen in the coatings varies from 6.3 to 33 at. %, which leads even at the greatest nitrogen content to the formation of lower phase by nitrogen, y-Mo₂N and isostructural CrN with the vacant sites in the nitrogen sublattice. The increase of thickness of the layers applied on the substrate in a stationary state promotes the increase of nitrogen content. Along with this, the lowest microdeformation and the average size of crystallites are formed at U_b = - 300 V, which defines the achievement of greater hardness of 35 GPa and high adhesion strength, which resists the destruction, L_c5 = 187.6 N. [ABSTRACT FROM AUTHOR]