A Novel, Amorphous, Non-equiatomic FeCrAlCuNiSi High-Entropy Alloy with Exceptional Corrosion Resistance and Mechanical Properties

The exceptional corrosion resistance and mechanical properties of high-entropy metallic glasses (HE-MGs) are highly desirable for diverse critical applications. However, a long-standing problem of these alloys is that their alloy design approaches are based on limited equiatomic or near-equiatomic ratios. In this study, a novel senary alloy (non-equiatomic Fe3Cr2Al2CuNi4Si5) with amorphous structure was prepared. This alloy exhibited exceptional corrosion resistance and Vickers hardness as high as ~ 1150 Hv at room temperature. The processing route involved amorphous powder molding via a mechanical alloying and ultrahigh pressure consolidation technique, resulting in an optimal microstructure of amorphous structure with nanoparticles uniformly distributed in the matrix alloy. This approach can effectively inhibit the crystallization of amorphous structure, thus providing a general pathway for manufacturing next-generation non-equiatomic HE-MGs with both exceptional corrosion resistance and strength.