Abstract
Metalloceramic Ni‑Al‑Fe / WC coatings were applied on AISI 1035 steel by the method of electrospark deposition using a non‑localized electrode consisting of millimetre‑sized iron granules and powders of aluminium, nickel, and tungsten carbide. The surface morphology and cross-sectional structure of the coatings, their phase and chemical composition, microhardness, wear resistance and oxidation resistance at a temperature of 700°C were studied. The coatings had a metalloceramic structure, where the reinforcing phases were tungsten carbide (WC) and tungsten subcarbide (W2C), while the metallic matrix was represented by intermetallic phases (NiAl, FeAl, Al86Fe14), and tungsten. With an increase in the aluminium to nickel ratio in the electrode from 1 / 4 to 4 / 1, the thickness of the deposited coatings increased from 25.1 to 48.8 µm, which is associated with the increasing effect of dilution of the layer by the iron from the substrate. Thus, the iron concentration increased from 30 to 51 at.% with an increase in the aluminium content in the electrode. The proportion of tungsten carbide in the coatings ranged from 32 to 54 vol.%. The microhardness of the coatings were in the range from 7.8 to 8.9 GPa. It has been shown that the application of Ni-Al-Fe / WC coatings can reduce the wear rate of products made of 1035 steel by 5.4 to 10.1 times and increase their oxidation resistance by 5.6 to 29.0 times. Reinforcement of the Ni-Al-Fe matrix with tungsten carbide using the proposed method allows obtaining coatings that combine high oxidation resistance and wear resistance.
Funding
1. The work was carried out within the framework of state assignment - No. 075-00399-25-04