Moscow Polytechnic University, Moscow, Russia:

R. A. Latypov, Head of the Department of Welding Equipment and Technology1, Doctor of Technical Sciences, Professor, e-mail: latipov46@mail.ru

Southwest State University, Kursk, Russia:
E. V. Ageev, Leader of the Research & Education Centre for Powder Metallurgy and Functional Coatings, Doctor of Technical Sciences, Professor, e-mail: ageev_ev@mail.ru
A. Yu. Altukhov, Head of the Department of Automobiles and Vehicle Fleet, Candidate of Technical Sciences, Associate Professor, e-mail: alt997@yandex.ru
E. V. Ageeva, Associate Professor at the Department of Automobiles and Vehicle Fleet, Candidate of Technical Sciences, e-mail: ageeva-ev@yandex.ru

Considering the standard procedure for producing globular powder particles, the authors of this paper propose to use the process of electroerosion dispersion for the production of globular particles of certain size for 3D technology. The proposed process is characterized with energy efficiency and sustainability. The waste cobalt-chromium alloy of the TsELLIT grade was used for the purposes of the study. Cobalt-chromium powders were produced by electroerosion dispersion on a special unit designed for conductive materials. Through experiments, it was established that as the particle dispersion rises, the baking process goes faster resulting in enhanced mechanical properties of the final products. Oxides present in fine-grained powders contribute to the intensity of the baking process as they are subject to reduction under heat impact. The spongy texture that forms when the oxides are gone from the metal surface appears to be more active compared with the oxide-film-free surface. The conducted study showed no changes to the structural and phase state of the specimens. Hence, all four specimens retained the following phases: Co, Cr, Ni и Cr₃Ni₂. The increasing dispersion and specific surface area of the powder leads to decreased porosity and increased microhardness in the final product. Due to the presence of particles of various sizes, the powder layer appears to be denser as cavities and micropores occurring between coarser particles get filled up. This results in lower roughness and higher compression and bend strength in baked parts. This study proves the possibility to control the structure and physico-mechanical properties of additive manufacturing parts made of powders that are obtained from waste cobalt-chromium alloys by electroerosion dispersion. This helps reduce the reliance on imported powders suitable for additive manufacturing while also cutting the cost of the final products.

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