Vladimir Ivanovitch Semenov

Polycrystalline HfZrO₂ (HZO) film can be fabricated on as-extruded Mg–Ca alloy, which is identified by the results of XRD and TEM. HZO film can improve the corrosion resistance of as-extruded Mg–Ca alloy to further result in a decrease in the corrosion rate of Mg–Ca alloy. Corrosion current density, pH value evaluation, and the corrosion surface image provide evidence of improvement in corrosion rate. Compared with ZrO₂ film, HZO film shows better short-term corrosion resistance. The results of WST-1 assay and LDH assay show that HZO film has low toxicity and is suitable for the protective coating of biological implants.

Using computer simulation in the DEFORM-3D software package, we performed a virtual full factorial experiment for the ECAP-Conform processing of the low-alloyed chromium bronze Cu-0.14%Cr. In the course of the experiment we evaluated the effect of independent parameters (the rotation speed of the working wheel, the friction factor at the lateral surfaces of the working wheel and the friction factor between a billet and the die). As a result of the experiment, we obtained a regression equation and determined the most important individual factors and their combinations that influence the response parameter – the deformation force.

The paper presents experimental data on the determination of the tribological properties of commercially pure titanium with different microstructures, with and without a coating. As a result...

In the present work, we report the results of tribological studies on commercially pure copper (Cu 99.9%) in contact a with graphitic material. The samples under study were made with two types of micro-structures, i.e., a coarse-grained (CG) microstructure with an average grain size of 20–60 μm after annealing and a submicrocrystalline (SMC) microstructure with an average grain size of 0.22 μm after severe plastic deformation (SPD) processing through equal-channel angular pressing (ECAP) via the Conform scheme. It has been shown that the SMC samples after ECAP-Conform processing reveal friction coefficients 12–20% lower than in the case of the annealed coarse-grained (CG) sample.

The work presents the results of tribological study of low-carbon steel (up to 0.2 wt % carbon) in three states: initial (hot-rolled), heat-treated (refined), and refined and further subjected to severe plastic deformation by equal-channel angular pressing. After the various treatment types, the steel samples are found to be in different structural states with different hardness values and oxygen content in the surface layer. These factors exert a complex effect on the material’s tribological properties in contact with tool steel. The lowest adhesive strength, friction coefficient, and wear rate are shown by refined and plastically deformed steel.