Corrosion resistance enhancement of CoCrFeMnNi high-entropy alloy fabricated by additive manufacturing

[Display omitted] •Equiatomic CoCrFeMnNi HEA was successfully fabricated by selective laser melting.•The composition uniformty and multi-scale microstructure characterization of the SLMed HEA were studied.•The SLMed CoCrFeMnNi HEA had better corrosion resistance than the as-cast CoCrFeMnNi HEA in NaCl solution.•The surface three-dimensional profile of the corrosion samples was characterized by laser scanning confocal microscope. A CoCrFeMnNi high-entropy alloy (HEA) was fabricated by additive manufacturing using selective laser melting (SLM). The corrosion behavior of the SLM-produced and as-cast CoCrFeMnNi HEA in 3.5 wt.% NaCl solution was comparatively analyzed. Compared to the as-cast HEA, more uniform composition and finer grains were observed in the SLMed HEA. The passive film formed on the SLMed HEA had a more stable and stronger protective property. The corrosion current density of the SLMed CoCrFeMnNi HEA dropped by 58 % compared to that of the as-cast HEA, indicating that the SLMed HEA had better corrosion resistance than that of the as-cast alloy.