Chemical inhomogeneities in high-entropy alloys help mitigate the strength-ductility trade-off

Metallurgists have long been accustomed to a trade-off between yield strength and tensile ductility. Extending previously known strain-hardening mechanisms, the emerging multi-principal-element alloys (MPEAs) offer additional help in promoting the strength-ductility synergy, towards gigapascal yield strength simultaneously with pure-metal-like tensile ductility. The highly concentrated chemical make-up in these “high-entropy” alloys (HEAs) adds, at ultrafine spatial scale from sub-nanometer to tens of nanometers, inherent chemical inhomogeneities in local composition and local chemical order (LCO). These institute a “nano-cocktail” environment that exerts extra dragging forces, rendering a much wavier motion…

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  National Natural Science Foundation of China