Structure and Properties of the "Cantor HEA Coating (Mn-Fe-Cr-Co-Ni) / Substrate (Alloy 5083)" System

Abstract

Using the technology of cold metal transfer (wire-arc additive manufacturing combined with welding surfacing), a coating is formed on a 5083 alloy substrate with a high-entropy Mn-Fe-Cr-Co-Ni alloy of nonequiatomic composition. Analysis of the structure, elemental composition, and microhardness of the coating-substrate system is carried out using the methods of modern physical materials science. A significant increase (up to 9.9 GPa) in the microhardness of the material is found in the zone of contact between the coating and the substrate. The formation of lamellar inclusions (Al13F4) enriched in coating atoms in the zone of contact between the coating and the substrate is revealed. The high entropy coating in the contact zone has a submicrocrystalline grain-subgrain structure with a crystallite size ranging from 0.5 ^m to 1.1 ^m along the boundaries where nanosized particles of the second phase (Al3Ni) are revealed. The volume of grains contains a dislocation substructure in the form of randomly distributed dislocations or dislocation clusters. The scalar density of the dislocations is (0.8-1.0)-1010 cm-2. An assumption is made about the physical mechanisms of hardening of the material in the "coating-substrate" contact zone. Key words: high-entropy alloy, coating / substrate system, aluminum alloy, elemental and phase composition, microhardness, hardening.