A supersaturated high-entropy alloy with both superior corrosion and mechanical properties

Abstract

As aerospace and marine engineering advance, alloys face increasingly stringent performance demands, particularly in corrosive environments. As a rule, introducing precipitates enhances alloy strength but often compromises corrosion resistance. This study achieved a synergistic improvement in both properties by controlling σ-phase precipitation through annealing temperature adjustments. 500 ℃ annealing enhanced mechanical strength via precipitation and dislocation strengthening, while optimizing beneficial oxides in the passive film improved corrosion resistance. Nevertheless, excessive annealing promoted large-scale precipitates, inducing microscopic galvanic corrosion and degrading overall performance. These findings offer insights into the composition design and industrial application of precipitation-strengthened high-entropy alloys (HEAs).