A Lightweight AlCrTiV 0.5 Cu x High-Entropy Alloy with Excellent Corrosion Resistance.

Lightweight high-entropy alloys (HEAs) are a new class of low-density, high strength-to-weight ratio metallic structural material. Understanding their corrosion behavior is crucial for designing microstructures for their practical applications. This work investigates the electrochemical corrosion behavior of lightweight HEAs AlCrTiV 0.5 Cu x ( x = 0, 0.2, 0.4, 0.6, 0.8, and 1.0) in a 0.6 M NaCl solution. These HEAs were produced by vacuum arc melting. In contrast to 304L stainless steel, all of the alloys exhibited lower current density levels caused by self-corrosion, with AlCrTiV 0.5 demonstrating the highest corrosion resistance (0.131 μA/cm 2 ). Corrosion resistance decreased along with the content of copper because copper segregation accelerated local corrosion throughout the alloy.