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We study the corrosion and tribocorrosion behaviors of hard alloys of the VN20 + Cr3C2 and VN20 + VC systems in solutions based on 3% NaCl with different рН values. In alkali media, the corrosion currents and friction coefficients are lower than in acid media, which is explained by the inertness of nickel. The VN20 + 1 wt.% Cr3C2 alloy has the highest corrosion and tribocorrosion characteristics.

We study the influence of external polarization with different potentials on the tribocorrosion behavior of 08Kh18N10T steel in contact with a corundum ball in a 3% NaCl solution. It is shown that the mechanical factor shifts the potential of pitting formation to the negative side by 0.17 V as compared with the surface without friction. The running-in time, friction coefficient, and material losses in the process of tribocorrosion qualitatively correlate with each other and depend on the applied electrode potential. It is shown that hydrogen released in the contact zone under the conditions of cathodic polarization embrittles the surface layers participating in the contact interaction. Moreover, hydrogen reduces oxide films and prevents their rapid formation on steel, which intensifies its wear. In addition, hydrogen facilitates deformation and increases the deformation zone near the friction track. Under the anodic polarization, we observe an increase in the number of pits in the friction area.

We study the influence of the contact speed of friction surfaces on the tribocorrosion behavior of D16Т alloy in acid rain. It is shown that the electrode potential, the friction coefficient, and the loss of material in the course of tribocorrosion qualitatively are well correlate and depend on the velocity of mutual displacement of the surfaces of friction couples. It is demonstrated that the activation potential, corrosion potential, and tribological potential enable one to estimate the fracture mechanism of materials passivated in corrosive media.

We study the corrosion and tribocorrosion properties of tungsten-carbide metal composites alloyed with graphite and chromium and vanadium carbides in a 3% NaCl solution. It is shown that the addition of 2–4% of graphite to the VN20 composite intensifies local corrosion processes because graphite inclusions serve as additional cathodic sections. This deteriorates the tribocorrosion behavior of the alloys, including the alloys alloyed with chromium and vanadium carbides because the corrosion processes in the contact zone lead to the crumbling of carbide inclusions playing the role of abrasive. We revealed the high wear resistance of the (VN20 + 1% VC)–(VN20 + 1% Cr3C2 ) friction couple in a 3% NaCl solution. After friction, the corrosion current density decreases on both contacting surfaces by almost an order of magnitude, which corresponds to the formation of secondary structures guaranteeing corrosion protection.

The tribocorrosion behavior of stainless steels in corrosive media is analyzed. Urgent problems of promising investigations in this direction are formulated.