DOI: 10.18503/1995-2732-2023-21-4-34-43
Abstract
Electrolytic chromium has high corrosion resistance, low friction factor, high hardness, heat resistance, and high yield stress. The said properties contribute to the widest possible application of the electrolytic chromium plating process in all the branches of mechanical engineering. The peculiarities of the electrolytic chromium plating process conventionally include low dissipation capacity of electrolytes of chromium plating and, consequently, one of the lowest metal current yield, high current densities, high sensitivity of the process to the process mode, need for using insoluble anodes, and the use of toxic hexavalent chromium-based compounds. Depending on the electrolysis conditions (electrolyte temperature, current density), chromium precipitates can demonstrate different physical properties, mainly in hardness and reflectivity. A large number of studies on electrochemical chromium plating are attributed to steels and copper alloys. At the same time, the promising area of surface chromium plating of titanium products needs thorough research. This paper proposes the compositions of two groups of electrolytes based on trivalent and hexavalent chromium compounds as basic compositions for studying electrochemical chromium plating of titanium products. We experimentally determined the values of density, viscosity, specific conductivity of the proposed solutions. Voltammetric studies on electrochemical processes were performed on the titanium electrode in the experimental electrolytes. It has been found that in the studied limits of titanium electrode potential changes the processes of changing the valence state of chromium had significant difficulties. The results obtained are the basis for a more in-depth study on the composition of electrolytes for electrochemical chromium plating of titanium products. They can also help study the features of kinetics of the chromium deposition on titanium by means of experimental electrochemistry.
Keywords
electrolytic chromium plating, electrolyte, titanium, voltammetry characteristics
For citation
Gruba O.N., Ardashev D.V., Degtyareva-Kashutina A.S. Physical and Chemical Properties of Electrolytes for Chromium Plating of Titanium Parts. Vestnik Magnitogorskogo Gosudarstvennogo Tekhnicheskogo Universiteta im. G.I. Nosova [Vestnik of Nosov Magnitogorsk State Technical University]. 2023, vol. 21, no. 4, pp. 34-43. https://doi.org/10.18503/1995-2732-2023-21-4-34-43
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