The particle size distribution significantly affects the material properties of the additively manufactured parts. In this work, the influence of bimodal powder containing nano- and micro-scale particles on microstructure and materials properties is studied. Moreover, to study the effect of the protective atmosphere, the test samples were additively manufactured from 316L stainless steel powder in argon and nitrogen. The samples fabricated from the bimodal powder demonstrate a finer subgrain structure, regardless of protective atmospheres and an increase in the Vickers microhardness, which is in accordance with the Hall-Petch relation. The porosity analysis revealed the deterioration in the quality of as-built parts due to the poor powder flowability. The surface roughness of fabricated samples was the same regardless of the powder feedstock materials used and protective atmospheres. The results suggest that the improvement of mechanical properties is achieved by adding a nano-dispersed fraction, which dramatically increases the total surface area, thereby contributing to the nitrogen absorption by the material.

Electrical explosion of aluminum wires has been shown to be a versatile method for the preparation of bimodal nano/micro powders. The energy input into the wire has been found to determine the relative content of fine and coarse particles in bimodal aluminum powders. The use of aluminum bimodal powders has been shown to be promising for the development of high flowability feedstocks for metal injection molding and material extrusion additive manufacturing.

In this research, Ti-Al powders were produced by electrical explosion of twisted titanium and aluminum wires. The resulting powders were pressed and sintered in a vacuum to obtain bulk composites. Transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), and X-ray diffraction (XRD) studies were performed to analyze synthesized powders and bulk composites. The studies carried out showed the presence of α-Ti, α₂-Ti₃Al, and γ-TiAl phases, which are formed by coalescence of Ti and Al clusters formed in the process of non-synchronous electrical explosion of twisted wires. Furthermore, an increase in the energy injected into the wires leads to a decrease in the content of micron particles in the powder. During sintering of pressed Ti-Al powder in the range 800–1250 °C, phase transformations occur due to the diffusion of aluminum atoms towards Ti compounds. The research findings can be used to obtain Ti-Al particles and bulk composites with a controllable phase composition.

Composites based on the MAX-phases are promising materials for wide range application. Composites MAX-phase–copper can be used in electrical engineering as wear-resistant and durable sliding contact materials. Such composites can be used as coatings on sliding contacts to improve local strength and wear-resistance without a significant increase in production costs. In this work, Ti${}_3$AlC${}_2$—nano-Cu composites with the ratio Ti${}_3$AlC${}_2$:Cu = 1:1 by weight or approximately 4:1 by volume were studied. The main task of the study is to obtain a dense structure, as well as to study the effect of the sintering temperature of the samples on their structure, phase composition, mechanical properties, and electrical conductivity. In addition, the sintered specimens were subjected to a hot isostatic pressing to possibly further increase the density. It was found that the best combination of strength, density, and electrical conductivity is achieved after sintering at 1050 °C. A further increase in the sintering temperature leads to an intensification of the MAX phase decomposition process, and at a lower sintering temperature, the copper matrix remains incompletely formed.

The hydroxyapatite synthesis on a variety of substrates under various conditions was studied. It was shown that the increase in the temperature of the reaction medium increases the amount of nanocrystalline phase with an average crystallite size of 25 nm. Studies revealed that in addition to the pure hydroxyapatite, β-Ca3(PO4)2 along with calcium carbonates and carbonate-substituted hydroxyapatites were formed. A significant increase in phase crystallinity during the heating of reactants up to the reaction temperature was shown.