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In the case of cathodic polarization due to flooding, plasticization of contact areas

is observed, which is manifested in the exit to the surface of the sliding strips, and,

despite the inhibition of anodic dissolution, an increase in material losses.

 It was found that the mechanisms of tribocorrosion of technically pure

metals (aluminum, copper, iron, nickel, niobium, zirconium, titanium) by hydrogen

depolarization determine the properties of secondary structures that are formed

during frictional interaction under the influence of hydrogen. It was recorded for

the first time that during the absorption-desorption of hydrogen in the surface

layers of armco-iron there is a crystallographic reorientation of subgrains, and also

the distribution of maximum internal stresses changes.

 It is shown that the combined action of flooding and friction

accelerates the diffusion processes in the amorphous nickel-phosphorus structure

of the coating, which promotes the formation in the surface layers of the

reinforcing phase of Ni3P, which increases its wear resistance. It was found that
the negative effect of hydrogen factor in tribocorrosion is manifested to a greater

extent with increasing hardness of heat-treated nickel electrochemical composite
coatings of the Ni – B system, which is associated with reduced cohesive strength

between structural components of the coating due to hydrogen.
 Chromates, which are effective corrosion inhibitors, have been found

to accelerate tribocorrosion of D16T alloy due to the formation of brittle secondary

structures. Instead, zinc phosphates increase the resistance of aluminum alloy to

corrosion and mechanical wear due to the formation of wear-resistant secondary

structures formed by mechanical and electrochemical factors.

 It is established that in contrast to classical tribology, during

tribocorrosion processes the coefficient of friction decreases with wear

intensification, due to changes in surface properties under the action of hydrogen

and corrosion factors and the formation of secondary structures.