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polarization intensifies the formation of secondary structures and increases wear.

The coefficient of friction decreases insignificant. It was shown for the first time

that the frictional interaction under anodic polarization initiates the shift of the

pitting potentials of the 08H18H10T alloy towards the corrosion potential. It is

established that the parameters of fine crystalline structure, phase composition and

micromechanical properties of surface layers of metals change due to electrolytic

hydrogenation, which determine their tribological behavior and wear mechanisms:

 It is shown that the concentration of residual hydrogen in the surface

layer of armco iron increases from 3 to 16 ppm with increasing current density

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from 0.5 to 2 A/dm . It causes embrittlement and destruction of the friction surface
by the dispersion mechanism. Therefore, in the conditions of dry friction, the wear

of pre-hydrogenated iron-armko increases by 40…60%, and in the case of friction

with simultaneous hydrogenation - by 10%.

 hydrogenation of aluminum and copper does not cause a significant

change in their tribotechnical characteristics. Copper and aluminum are

characterized by oxidative wear, which is insensitive to hydrogen.
 titanium interacts with hydrogen and brittle hydride phases are

formed , which reduce the wear resistance of the metal both after hydrogenation

and in its process. The friction force during the scratch tests is reduced by ~ 3

times, and the material losses increase by 30-50%.
 hydrogenation of niobium to a concentration of more than 10 at. %

leads to the strengthening of the surface layer and, accordingly, increase its wear

resistance by ~ 4 times.

 hydrogenation of zirconium to a concentration of ~ 5 at. % reduces its

wear resistance by 20….40%. In the presence of hydrogen in the surface layers, a

hydride phase is formed, which serves as a solid lubricant and increases the wear

resistance of zirconium both after and during the hydrogenation process.

It was found that galvanic composite coatings Ni-P and Ni-B after heat

treatment reduce wear of steel 17Mn1Si in 2-5 times in a hydrogen environment

and wear of aluminum alloy Д16T in a chloride-containing environment in ~ 7