Cold rolling and annealing-induced structural and corrosion modifications in (FeCoNi)75Cu10Cr15 high-entropy alloy

Purpose The purpose of this study is to investigate the structural, microstructural, mechanical and electrochemical behavior of a (FeCoNi)75Cu10Cr15 high-entropy alloy (HEA) under different processing conditions, including as-cast, cold-rolled and annealed states. The aim is to evaluate its potential for corrosion-resistant applications. Design/methodology/approach The alloy was synthesized using vacuum arc melting, followed by 55% cold rolling and annealing at 900°C for 1 h. X-ray diffraction (XRD) was used to analyze phase structure and texture development. Scanning electron microscopy (SEM) was used for microstructural characterization. Mechanical hardness was measured using a Vickers hardness tester. Electrochemical corrosion behavior was evaluated in 1 M H2SO4 using an electrochemical workstation. Findings The results showed a stable face-centered cubic (FCC) structure in all processing states. Cold rolling introduced {111}<112> and {110}<100> texture components and transformed equiaxed grains into elongated, textured structures with discontinuous Cu-rich regions. Annealing resulted in slight coarsening while maintaining directional features. The hardness increased from 124.3 ± 0.7 HV (as-cast) to 285.7 ± 10.1 HV (rolled), and slightly decreased to 251.9 ± 2.6 HV (annealed). Electrochemical measurements revealed improved corrosion resistance after processing, with impedance values rising from 2,633 Ω (as-cast) to 3,709 Ω (rolled) and further to 5,972 Ω (annealed). Originality/value This study demonstrates that thermomechanical processing significantly enhances both the mechanical strength and corrosion resistance of (FeCoNi)75Cu10Cr15HEA.