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Friction cladding as one of the simplest methods of surface modification with simultaneous coating application was used for surface nanostructuring. Intensive plastic deformation using a rotating wire brush (RWB) was performed during friction cladding. Brush fibers had an impulse-friction effect on the work surface with simultaneous coating application. Normalized steel samples (diameter 45 mm, width 10 mm) made of Grade 45 steel were tested for wear resistance. A copper-containing coating was applied at a circular grinder. Samples treated by various operating modes were tested at the SMC-2 friction machine using a disk-to-disk friction drive scheme. The tests showed that samples with a copper coating (C1) and a brass coating (B63) feature 2–10 times higher wear resistance in comparison than reference ones depending on the treatment mode. Samples with a brass coating (coating thickness 10–15 μm) applied in 6 passes with 2 mm interference (RWB feed on the work piece) at a sliding speed of 25 m/s demonstrated the highest strength. Smooth specimens (four series, a total of 60 pieces) made of 20CN steel were tested according to GOST 25502-82 «Fatigue Test Methods» to study the effect of friction cladding modes on endurance. Test results showed that the most effective way is surface plastic deformation with brass coating application. The endurance limit increase factor was Kυ = 1,41. It was found that steel mechanical properties (σв, σт, δ10) are not affected by coating application using friction cladding. Copper coating applied on coupling rods and plungers in hydraulic systems ensured 1,4–3,0 times longer service life, and up to 6 times longer life when applied on wave gear teeth in edge version.

The carrying capacity of prestressed joints may be increased by plastic deformation of one surface using a flexible tool (rotating wire brush) and simultaneous coating application to that surface. An aluminum coating increases the frictional coefficient in the joint. Impact-friction treatment or dynamic cold working by hammer faces creates a strengthened nanostructured layer.

Results are presented from studies of the effect of certain processing factors on the strengthening, reconditioning, and protection of surfaces through the application of coatings by friction cladding. It is established that the use of an electric current speeds up the process, significantly increases the thickness of the coating, and improves its ductility. Combination treatment that entails knurling followed by the application of a functional coating with a flexible tool makes it possible to increase the diameter of a worn part and form an ultrafine-grained structure in its surface layer as a result of intensive plastic deformation.

The microstructure and properties of the functional coatings formed by impact friction processing of product surfaces with a flexible tool are studied. It is established that the processing produces a hard nanostructured surface layer with fragments up to 0.13 µm in size, as it is achieved by severe plastic deformation.

Theoretical and technological principles have been developed for the plastic deformation of the surface layer, with simultaneous application of a metal coating, by means of a flexible tool. This process is known as frictional plating. Resource-saving and environmentally benign technologies have been created for the manufacture of metal components with improved performance.