The growth of dendritic deposit under galvanostatic electrolysis is modeled and a method is developed to analyze its formation in laboratory. The time dependences for cathodic overpotential are plotted and the rod electrode with deposit is video-recorded to establish that copper dendrites form at smaller tip-radius density from the solution with surface-active agent F2 than from the solution without additions. This results in higher fluidity of the powder. Nevertheless, dendrites formed from the solution with F2 addition have greater tip radii than the deposit from the pure solution. In addition, the dendritic deposit intensively grows for a longer time with F2 addition, thus increasing the yield of powder and decreasing the yield of cathodic scrap. The results from the laboratory experiment have been confirmed by commercial production.

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The article is devoted to the description of a method for producing electrolytic copper powder with an average particle size of 3 to 10 μm. In order to increase the proportion of the finely dispersed fraction during the electrolysis process, the composition of the electrolyte was changed. In particular, the content of chloride ions was increased from 6 to 53 mg/dm3. After the growth of the powder in industrial baths, its subsequent drying and sieving on vibrating screens, samples were obtained with a fraction of 5 μm content in the range from 3 to 38 %. Additionally, air classification of powders was carried out at various speeds of the classifier rotor from 800 to 2000 rpm. Based on the results of the study, the optimal ranges of the specific surface area and the size of the initial powder particles before classification, as well as the composition of the electrolyte and the operating modes of the classifier, were determined.