Characteristics of Iron-Based Metallic Glass Coatings Reinforced with Al2O3

Abstract

Using electrical discharge machining (EDM) with a non-localized electrode, FeCrWMoSiCB/Al₂O₃ composite coatings of iron-based metallic glasses with aluminum oxide were prepared for grade 35 steel. Coating thicknesses ranged from 36.6 to 48.8 μm. X-ray diffraction patterns of coatings reveal a broad halo, indicating the predominance of the amorphous phase. Elemental mapping data indicate a dispersed distribution of Al₂O₃ particles in the coating. The coating surface exhibited high hydrophobicity, with distilled water contact angles of 108°–127°. An increase in corrosion potential and a decrease in corrosion current density were demonstrated with the introduction of aluminum oxide into the amorphous matrix. Impedance spectroscopy data indicate an increase in the density and stability of barrier film formed in the electrolyte with the introduction of Al₂O₃ into the metallic glass. Heat resistance at 700°C for composite coatings with aluminum oxide was lower than for samples with metallic glass coatings. Tribological tests showed a twofold increase in wear resistance of coatings with dispersion hardening of the amorphous matrix with aluminum oxide.