Keyword: «borides»
In this paper, the processes of structure formation during gas-thermal electric arc metallization with powder wire are considered. The basic composition of the charge is nickel alloy PGSR-4. Niobium powders were selected as modifying additives, the content of which in the charge of powder wires is: 0.1%, 0.3%, 1% and 5% by weight. The influence of niobium content on carbide formation, on the ratio of structural components, on the formation of oxide phases, and the dispersion of the surfacing microstructure are shown. Tribological studies have shown that the wear of samples decreases by an order of magnitude, starting with the addition of 0.3% niobium. With a niobium content of 1% and 5% in the powder wire, the wear resistance remains high, but the mass losses of the samples and the counterbody are balanced, which is due to the grinding of the microstructure and an increase in the uniformity of micromechanical properties.