## 2 Materials and Methods  
For the manufacturing of the 3D metal objects, layer-by-layer deposition of the powder of a Fe-Cr-Ni-B-Si system on the metal substrates from AISI 304 steel with dimensions of approximately 100 \(\times\) 100 \(\times\) 10 mm was performed. The chemical composition of the substrate material and powder is given in Table 1. A batch feeder of the original design was used for the filler powder feeding to the plasmatron. In order to conduct deposition, preliminary preparation of the filler powder was performed as follows: heating at the temperature of 150 \(\dots\)200 \({}^{\circ}\)C to remove moisture and calibration by sifting in a set of special sieves. The particle size distribution of the powder was checked via optical microscopy, and its chemical composition was verified via scanning electron microscopy. Investigations of the particle size distribution of HYF-103 powder showed its inhomogeneity. This powder consists both of coarse and fine particles of predominantly spherical shape (Figure 1). Their size varies from 15.39 \(\upmu\)m to 67.85 \(\upmu\)m. The mean size is 39.88 \(\upmu\)m. The size of some particles is 109.45 \(\upmu\)m. Investigations of oxidized powder showed the stability of its chemical composition (Table 2). For the selection of the powder material for deposition, the following aspects were taken into account. In keeping with ref. [20], the deposition of the powder material of the Fe-Mn-C-B-Si-Ni-Cr system promotes the segregation processes, which is revealed by investigations performed by the methods of X-ray photoelectron spectroscopy and X-ray diffraction analysis. So, during friction as a result of tribological testing, the segregation of C, B, and Si atoms was observed. The presence of the following compounds was recorded in the subsurface layers: oxides (B\({}_{2}\)O\({}_{3}\), SiO\({}_{2}\), Cr\({}_{2}\)O\({}_{3}\)); carbides (Fe\({}_{3}\)C, Cr\({}_{7}\)C\({}_{3}\)), and borides (FeB, Fe\({}_{2}\)B). This is indicative of intensification of the processes of phase formation as a result of deformation effects. The formation of such structures improves the wear resistance \begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Material**} & \multicolumn{1}{c}{} & \multicolumn{1}{c}{} & \multicolumn{1}{c}{**Element Content, wt. \%**} & & & & & & \\ \cline{2-10}  & **Fe** & **B** & **C** & **Si** & **Mn** & **Ni** & **Cr** & **Cu** & **P** & **S** & **Other** \\ \hline \multicolumn{10}{c}{Substrate metal} \\ \hline AISI 304 steel & Base & – & \textless{}0.8 & \textless{}0.8 & \textless{}0.2 & 9–11 & 17–19 & \textless{}0.3 & \textless{}0.035 & \textless{}0.02 & Ti \textless{} 0.5 \\ \hline \multicolumn{10}{c}{Filler (deposition) materials} \\ \hline HYF–103 powder (40–60 \(\upmu\)m size) & Base & 1.15 & – & 0.75 & 0.6 & 7.85 & 15.55 & – & \textless{}0.02 & \textless{}0.01 & – \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Chemical composition of the applied materials. of the coating material. The intensification of phase formation processes will enhance the structural strengthening of the deposited metal. Such a process may also influence the level of local internal stresses in the surface layer structure due to the redistribution of crystalline lattice defects. Here, nanophase particles are formed [21]. The uniform distribution of dispersed particles of strengthening phases in the deposited metal matrix will promote the gradientless distribution of the dislocation density. It will prevent the formation of local internal stress raisers: cracking centers [22]. The appearance of large phase formations, however, may promote the development of dislocation clusters with their higher density. Such a structural state may lead to the formation of zones of deformation localization and an abrupt increase in the level of local internal stresses in these structural zones [23]. This, in turn, will lead to cracking in the deposited layer material. In ref.