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It has been found that the nanocrystalline surface layer serves as a barrier for
hydrogen penetration into the bulk material. The surface layer with nanocrystalline
structure formed on the 45 steel by mechanical-pulse treatment is characterized by
lower hydrogen permeability (hydrogen diffusion coefficient is in 1.3–4 times
lower) and higher in 1.5–4.4 times efficiency of hydrogen trapping in comparison
with the untreated steel. Therefore, it serves as a barrier for hydrogen penetration
into the bulk material. It has been established that nanostructurization of the steel
surface using mechanical-pulse treatment by multidirectional deformation in an oil
technological medium provides the highest resistance of the steel to hydrogen
embrittlement.
It has been shown that adding nickel, boron and nitrogen-containing
substances into technological environment during mechanical-pulse treatment of
the carbon steels 35 and 45 increases their resistance to corrosion and can offset
the negative influence of intensive plastic deformation on corrosion resistance of
these steels in a corrosiion environment.
Friction coefficient and temperature in friction contact zone decreases
significantly after mechanical pulse treatment of surface of carbon and low-alloyed
steels. The surface layer of the 35 steel with nanocrystalline structure in a
tribological pair with the ШХ15 steel is characterzed by 8% lower friction
coefficient under dry friction in comparison with that of the untreated 35 steel. It is
decreased in almost 4 times for the 45 steel with surface nanocrystalline structure
under oil wear. The decrease in the coefficient of friction after mechanical pulse
treatment of steels correlates with the decrease in crystallite size on the surface.
Temperature in the zone of friction contact of a friction pair of the 40X steel with a
surface nanocrystalline structure is lower than that of a friction pair of the 40X
steel without a nanocrystalline structure, which has a positive effect on wear
resistance.
The nanocrystalline surface layer is characterized by high wear resistance
under oil and oil-abrasive wear, as well as, under the action of the corrosive-
hydrogenating medium of diethyl glycol. The highest wear resistance of the