Achieving simultaneous wear and corrosion resistance remains challenging for protective coatings exposed to mechanically aggressive and corrosive environments. In this study, Mo-WB₂-NiCr composite coatings containing 0-20 wt.% Mo were fabricated by laser cladding to investigate the effect of Mo on their microstructure, wear, corrosion, and tribocorrosion behavior. Mo addition refined the solidification structure and increased hardness, whereas excessive Mo promoted chemical heterogeneity. NWM10 (10 wt.% Mo) exhibited the lowest dry-wear rate of 1.37×10^-6 mm³/(N·m), 61.4% lower than that of NWM0, together with the lowest corrosion current density of 0.152 μA/cm². During tribocorrosion, repeated depassivation-repassivation governed the interfacial performance, accompanied by the formation of Cr-, W-, and Mo-containing oxides. NWM10 exhibited the lowest cumulative material loss under both OCP and -0.2 V vs. Ag/AgCl, although NWM15 showed the lowest instantaneous current density and friction coefficient under the imposed potential. These results demonstrate that optimal tribocorrosion resistance arises from balancing mechanical strengthening, microstructural uniformity, and surface-film stability rather than maximizing any single mechanical or electrochemical property.

Laser cladding; Composite coating; Ceramic particles; Dry friction; Electrochemical corrosion; Tribocorrosion