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surface layer of the 40X steel with nanocrystalline structure in friction pairs with
cast iron ВЧ60 and bronze БРаЖН is provided by mechano-pulse treatment in oil
technological medium. High wear resistance remains even after heating to 300 ° C.
Wear resistance of friction pair of the 40X steel with surface nanocrystalline
structure – cast iron ВЧ60 in the corrosive-hydrogenating medium (diethylene
glycol) is significantly higher than that of friction pair of the 40X steel after
quenching and tempering at T = 200 ° C – bronze БРаЖН, which makes cast iron
an effective alternative to bronze in friction pairs in diethylene glycol.
The surface nanocrystalline layer significantly increases fatigue and
corrosion fatigue boundaries, as well as contact fatigue durability of pearlite low-
alloyed steels. The usage of mechanical pulse treatment, followed by rolling with
rollers to form a surface nanocrystalline structure on the 50ХН and 60Х2М roller
steels increases their resistance to fatigue (in 1.4 – 1.6 times) and corrosion-fatigue
(in 2.6 – 3.1 times) fracture and enables achieving the same level of corrosion-
fatigue durability that is inherent to the steel in the as-received state tested in air,
that is completely offset the negative impact of corrosive environment. This
increase is achieved by the surface nanocrystalline structure formed in the surface
layers, residual compression stresses, and favorable redistribution of the alloying
elements.
The applying of mechanical pulse treatment for the formation of surface
nanocrystalline structure on the 60X2M steel in combination with pre-quenching
and tempering at T = 450 ° C increases its contact durability and wear resistance
by 3.6 and 1.8–2 times, respectively.
The surface nanocrystalline layer formed by mechanical pulse treatment at
optimal regimes on the 65Г steel increases its contact durability by 1.4 – 2.1 times
compared to that of samples after quenching and tempering at 200 ° C; it depends
on the parameters of the nanocrystalline structure, namely the size of the
crystallites on the surface, the thickness of the hardened layer and its
microhardness.
Nanocrystalline surface layer formed by mechano pulse treatment on the