Abstract
<jats:p>ABSTRACT: The article presents the results of testing nanocomposite electroplating based on chromium for wear resistance and corrosion resistance. The studied nanocomposite coatings were obtained by co-deposition with nanoscale aluminum oxide particles. The nanoscale particles had a spherical shape and dimensions of 10...100 nm. The production of nanoscale particles with such parameters was achieved by plasma recondensation of the feedstock. Chromium electroplating coatings were applied from a self-regulating chromium plating electrolyte in hard chrome plating modes. In order to ensure high sedimentation resistance of the electrolyte suspension, nanocomposite coatings were applied under constant exposure to ultrasound with a frequency of 18 kHz.Tribological tests of the samples were carried out on a friction machine according to the "roller – pad" scheme according to GOST 23.224–86. Corrosion tests of the studied coatings were carried out on a laboratory installation by immersion of the studied samples in a saline solution in accordance with GOST 9.308-85.As a result of laboratory wear resistance tests, it was found that nanocomposite electrolytic coatings based on chromium have a wear resistance 1.5–1.8 times higher than the wear resistance of base coatings of chromium and 2.1–2.2 times higher than the wear resistance of steel SHX15. The corrosion resistance of the chromium-based nanocomposite coating is 1.86 times higher than the corrosion resistance of the chromium base coating and 6.86 times higher than the corrosion resistance of 15X steel.Given the high wear resistance and corrosion resistance of chromium-based nanocomposite electroplating coatings, they should be recommended for use in machine-building and repair production as a way to restore worn parts and strengthen new ones. Additionally, it was found that the introduction of ultrasound exposure contributes to a more uniform distribution of nanoparticles in the electrode layer, reducing agglomeration and improving the adhesion of the coating to the substrate. This leads to a reduction in the coefficient of friction and an increase in the stability of performance under cyclic loads. The results obtained confirm the prospects of optimizing deposition modes to further enhance the functional properties of composite chrome coatings in conditions of elevated temperatures and aggressive environments, as well as to expand the scope of their industrial applications in mechanical engineering and repair.</jats:p>