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The influence of the architecture of multilayer metal-carbon coatings, the nature of individual metallic layers (Ti, Cu), heat treatment parameters on their microhardness, the level of internal stresses and tribotechnical properties are determined. It is defined that for systems based on carbon and nanosized metal layers, the friction coefficient values are lower than for single-layer carbon coatings. Heat treatment of multilayer systems in air leads to the increase in the friction coefficient, primarily Ti/a-C/Ti coatings, which is due to the formation of solid phases of TiN, TiC and TiCN, as well as oxides of TixOy acting as abrasive. The level of internal stresses of multilayer systems containing layers of copper is lower than that of single-layer carbon coatings and coatings containing layers of titanium.

The article considers morphology, chemical and phase composition of composite boro-carbon coatings, received by ion-plasma synthesis, depending on the boron content. Specimens of carbon coating doped with boron were obtained in vacuum unit by combined method coupled with co-deposition of carbon layer from pulse carbon plasma and its doping with boron atom flow. The obtained specimens of composite CC had embedded boron atoms with various concentration (NB), namely, 2.3 at.% were contained in ɑ-С91.2:B2.3, in ɑ-С79.3:B17.4 — 17.4 at.%, in ɑ-С53.3:B43.2 — 43.2 at.%. Carbon structures and carbon clusters graphitization were examined by X-ray photoelectron spectroscopy and Raman spectroscopy. Aiming at chemical interaction between carbon and boron in CC establishment we conducted mathematical processing of XPS for energy states C1s, B1s, O1s of carbon, boron and oxygen atoms. XPS C1s was presented as peaks superposition with centers located at 284.5; 285.5; 283.5 and 288 eV and consequently responsible for Csp2 , Csp3, C–B and C–О carbon atom interaction. With the growth of NB in boron-doped carbon coating a grain structure is formed, its size and grain orientation regarding the surface of the substrate increase, resulting in a decrease in the coating layer surface roughness.

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An acoustic method for quality control of adhesive compounds of polymer coating on metal in the coating—positive system qualitatively characterizing the value of the adhesive bond is proposed. Ultrasonic measuring cell is considered as a resonant system, the parameters of which are determined by the properties of all the parameters of the layered structure at the same properties of the piezoelectric sensor and acoustic contact. The coating adhesion is evaluated on the basis of the parameters of the amplitude-frequency characteristics of the studied layered structure of the composite coating according to the humming dependences of the adhesion — reflection coefficient the wave. The technique allows to control the processes of polymerization of organic coatings in the process of their formation.