A novel Cu-doped high entropy alloy with excellent comprehensive performances for marine application

Abstract High entropy alloy (HEA) has attracted great interests as one of the promising multifunctional materials in marine applications. However, Cu as an effective biocide tends to form segregation in HEA, which could deteriorate corrosion and induce brittle fracture. Herein, we report a strategy to tailor the existing form of Cu in HEA from undesired large-scale segregation to uniform distribution with dispersed nanoscale precipitation, while retaining the unique structure characteristics of HEA. Eliminating Cu segregation improves toughness and avoids serious corrosion in the grain boundary. Uniform distribution with dispersed nanoscale precipitation of Cu further enhances the antifouling and lubricating abilities of Cu-doped HEA. Tailored AlCoCrFeNiCu0.5 HEA in this work has excellent comprehensive properties combining good mechanical properties, outstanding antifouling abilities, superior resistance to corrosion and wear. Furthermore, the corresponded mechanisms are discussed in terms of Cu-segregation-eliminated, nanoscale-Cu-precipitate-forming and comprehensive properties.