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Fabrication of high-entropy alloys (HEAs) is a crucial area of interest for materials scientists since these metallic materials may have many practical uses. Wire arc additive manufacturing (WAAM), unlike other additive technologies, has tangible benefits for making large-sized components, but manufacturing the wire from HEAs is still very limited. Recent studies suggested tackling this problem using a combined cable composed of wires consisting of pure elements as feeding material. However, not all compositions of HEAs can be obtained by the pure elements’ wires because the number of them is limited. This study aims to examine phase composition, chemical elements distribution, microstructure, and mechanical properties of a Co-Cr-Fe-Mn-Ni HEA, which was not previously obtained by the WAAM. The cable-type wire used in this study is composed of two wires which consist of Cr, Fe, Mn, and Ni, and one pure Co wire. The phase composition, chemical elements distribution, microstructure, and mechanical properties were investigated. The prepared high-entropy alloy has non-equiatomic chemical composition with a single-phase FCC crystal structure with homogeneously distributed elements inside the grains. The microstructure examinations showed dendrite structure which is typical for WAAM processes. The compressive yield strength of the alloy is ~279 MPa, the ultimate compressive strength is ~1689 MPa, the elongation is 63%, and the microhardness is ~150 HV, which was found to be similar to the previously fabricated Co-Cr-Fe-Mn-Ni alloys by other methods. Fracture analysis confirmed the ductile behavior of deformation by the presence of dimples.

High-current pulsed electron-beam (HCPEB) surface modification of Al-Co-Cr-Fe-Ni high-entropy alloy (wt. %) Al—15.64; Co—7.78; Cr—8.87; Fe—22.31; Ni—44.57, fabricated via wire-arc additive manufacturing was studied. The initial condition of the sample is characterized by a highly inhomogeneous distribution of the chemical elements that form the alloy. The alloy samples were irradiated with the different electron beam energy densities of 10, 20 and 30 J/cm2. The surface structure was then analyzed in relation to an energy deposition mode. The study has established that HCPEB induces a high-speed crystallization structure with cells varying in size from 100 to 200 nm. There are nano-dimensional (15–30 nm) second-phase inclusions enriched with atoms of Cr and Fe along the grain boundaries. The most liquating elements are Cr and Al. Electron beam surface modification of the high-entropy alloy induces its homogenization. The study has highlighted that the mode of 20 J/cm2, 50 µs, 3 pulses, 0.3 s−1 results in the formation of a surface layer with the most homogenously distributed chemical elements.

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