Browsing by Author "Zabludovsky, Vladimir A."
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Item Adhesion Strength of Electrodeposited Ni, Zn, and Fe Coatings with Copper Substrates(Taylor & Francis Online, 2022) Shtapenko, Eduard Ph.; Zabludovsky, Vladimir A.; Tytarenko, Valentyna V.ENG: This paper presents the adhesive strength values of electrodeposited nickel, zinc, and iron coatings on copper substrates at various deposition parameters, including laser-assisted stimulation of the deposition process. One of the factors determined to be responsible for the adhesive strength of metal films with a metal substrate is the formation of a diffusion zone at the ‘coating-substrate’ interface. It is shown that an increase in adhesive strength is achieved due to the expansion of the diffusion zone and the formation of solid solutions. The decrease in adhesive strength at high overpotentials is associated with the release of hydrogen and the formation of intermediate phases.Item Adsorption of Co, Ni, Cu, Zn Metal Ions on Fullerene C60 and on Single-Wall Carbon Nanotubes C48 as a Driven Force of Composite Coatings’ Electrodeposition(Oles Honchar Dnipro National University, 2021) Tytarenko, Valentina V.; Shtapenko, Eduard Ph.; Voronkov, Eugene O.; Vangara, Aruna; Zabludovsky, Vladimir A.; Kolodziejczyk, Wojciech; Kapusta, Karina; Okovytyy, Sergiy I.EN: Composite electrodeposited films fabricated from aqueous solution of electrolytes that contain ions of metals along with carbon nanomaterial particles such as fullerene C60 were investigated. Results for the cathodic polarization curve showed an increase in charge-transfer resistance. Phase composition analysis for metal films revealed the presence of carbon nanoparticles (CNPs) inside the metal matrix and significant changes in the crystal lattice. As it shown on microphotographies, addition of CNPs changes columnar growth patterns of metallic films to microlayered structure due to passivation of the surface. Density Functional Theory was used for calculation of thermochemical, electronic and structural properties of metal ions complexes with CNPs. Calculated binding energies of the CNPs-Me2+ complexes suggests that an adsorption of Co2+, Ni2+, Cu2+, and Zn2+ ions on the surface of fullerene C60 and SWNT C48 is possible and thermodynamically favorable. Binding affinity was found to be significantly stronger when the metal ion was adsorbed onto a surface of SWNT C48, than adsorption to the fullerene C60. With Cu2+ complexes being the most thermodynamically stable, binding affinities were increasing in a row Co2+Item Application of Pulse Current for Producing a Strengthening Composite Nickel Coating(Eugen G. Leuze Verlag, 2019) Tytarenko, Valentyna V.; Zabludovsky, Vladimir A.; Shtapenko, Eduard P.; Tytarenko, Igor V.EN: Carbon-containing nickel coatings deposited with use of pulse current from aqueous electrolyte solution comprising ultradispersed diamond particles were studied. Effect of pulse current on concentration and distribution of co-deposited nanodiamond particles through a metal substrate matrix, structure, mechanical and resistance properties of composite electrolytic coatings was analyzed. It was demonstrated that application of new generation additives, more specifically nanocarbon ones, provides opportunity for improving physicochemical properties of coatings. During pulse mode of deposition fine-grained coatings are formed with microlayer growth structure in cross section that enhance their microhardness, wear strength and corrosion resistance.Item Diffusion at the Film-Substrate Interface During Nickel Electrocrystallization on a Copper Substrate(ФГУП "Наука", Москва, 2018) Shtapenko, Eduard F.; Zabludovsky, Vladimir A.; Tytarenko, Valentina V.EN: The results of experimental studies of the diffusion layer at the interface between a nickel electrolyte film and a copper substrate are presented. Studies have shown that in the transition layer, diffusion of the deposited metal into the substrate material occurs. The depth of the diffusion layer and, consequently, the concentration of interstitial nickel atoms strongly depend on the electrocrystallization conditions: 2 μm in the constant-current mode and 4 μm under laser-assisted deposition. The diffusion coefficient of nickel adatoms in polycrystalline copper is 8.3 × 10–16 m2/s in the constant-current deposition mode and 3.3 × 10–13 m2/s under laser-assisted deposition.Item Kinetic Regularities of the Formation of Composite Electrolytic Coatings Containing Ultradispersed Diamond Particles(Vasyl Stefanyk Precarpathian National University, Ukraine, 2022) Tytarenko, Valentyna V.; Zabludovsky, Vladimir A.; Shtapenko, Eduard Ph.; Tytarenko, Igor V.ENG: The paper formulates the problem of joint electrolytic co-deposition of metal ions and ultradispersed diamond particles into a metal matrix. It presents the developed mathematical model that describes the mechanism and kinetics of the cathode process, mass transfer of metal ions and ultradispersed diamond particles. A satisfactory correlation with experimental data was obtained. The contribution of the thermal action of laser radiation to the intensification of the process of co-deposition of dispersed particles and metal ions was determined. It was found that the more intense penetration of dispersed phase particles into the forming coating during the laser stimulation of the electrodeposition process is due to the presence of a temperature gradient, which provides an additional supply of metal ions in the irradiation region. Based on the theoretical and experimental studies, we established the regularities of the influence of the number and size of nanoparticles on the strengthening properties of composite metal coatings. It was found that an increase in the temperature of an aqueous electrolyte solution in the cathode region during a laser-stimulated deposition process leads to an increase in the flux density of ultradispersed diamond particles, and, as a result, to an increase in the concentration of the dispersed phase in nickel composite coatings, which contributes to the formation of a finer crystalline structure of coatings, an improvement in adhesion, strength properties and increased wear resistance of coatings.Item Laser-Enhanced Electrodeposition of Nickel Coatings(Taylor & Francis Group, London, 2017) Zabludovsky, Vladimir A.; Tytarenko, Valentyna V.; Shtapenko, Eduard P.EN: A method for producing the composite nickel coatings with a programmable pulse current with the changing from one layer to the concentration of particles in the metallic matrix of nanodiamonds. It is shown that this program allows layer-coating with the lowest concentration of nanodiamond in the first coating layers and increasing in subsequent layers, which improves adhesive properties, increases wear resistance and lowers the cost of dispersed particles of nanodiamond.Item Model of Dispersed Phase Particle Distribution in a Composite Electrolytic Coating(Springer Science + Business Media, США, 2020) Tytarenko, Valentina V.; Zabludovsky, Vladimir A.; Shtapenko, Eduard Ph.EN: A model is proposed to evaluate distribution of dispersed phase particles in a composite metal coating. This model is based on calculation of degree of surface occupation by particles and their distribution in volume. Effective parameters applied for electrolytic composites evaluation at the microscale level were formulated, and method for the parameters evaluation was set out. It was shown that density of distribution and portion of particles with certain size in a coating depend on electrodeposition modes. Generation of higher-fine crystalline close-packed structures of coatings in conditions of pulse relative duration increase from 2 to 50 and unchanged current frequency 50 Hz is caused by both increase of oversaturation at the crystallization front that results in higher non-equilibrium process of crystallization and also by passivation effect of UDD particles on the surface which is formed. Non-equilibrium conditions of crystallization give rise to more intensive penetration of disperse phase particles with smaller size (~ 0.25–1 μm) into growing coating, decrease of microlayers thickness from 4 to 2 μm and increase of UDD particles concentration from 1.43 to 2.47 mas.%.Item Pulse Current Electric Rhodium Plating(Eugen G. Leuze Verlag, 2021) Shtapenko, Eduard Ph.; Zabludovsky, Vladimir A.; Tytarenko, Valentina V.; Garnich, Ruslan Ph.EN: The paper covers the study of the structure and properties of rhodium coatings obtained by pulse current from an aqueous electrolyte solution containing no surfactants. The authors determined the optimal parameters of the pulse current that forms finer-crystalline, dense and hard coatings. The use of pulse unipolar current made it possible to obtain high-quality rhodium coatings without the use of surfactants.