Multicomponent intermetallic nanoparticles and superb mechanical behaviors of complex alloys

TLDR

Alloy design based on single‑principal‑element systems has reached its performance limits, and pushing strength to gigapascal levels typically causes premature failure due to reduced ductility. The study proposes a strategy to overcome the strength–ductility trade‑off by introducing high‑density ductile multicomponent intermetallic nanoparticles into complex alloys. The authors achieve this by controllably incorporating these nanoparticles into the alloy matrix. The resulting alloys reach 1.5 GPa strength with up to 50 % tensile ductility, eliminate plastic instability through multistage work‑hardening driven by dislocation activity and microbands, and offer a paradigm for next‑generation structural materials.

Abstract

Alloy design based on single-principal-element systems has approached its limit for performance enhancements. A substantial increase in strength up to gigapascal levels typically causes the premature failure of materials with reduced ductility. Here, we report a strategy to break this trade-off by controllably introducing high-density ductile multicomponent intermetallic nanoparticles (MCINPs) in complex alloy systems. Distinct from the intermetallic-induced embrittlement under conventional wisdom, such MCINP-strengthened alloys exhibit superior strengths of 1.5 gigapascals and ductility as high as 50% in tension at ambient temperature. The plastic instability, a major concern for high-strength materials, can be completely eliminated by generating a distinctive multistage work-hardening behavior, resulting from pronounced dislocation activities and deformation-induced microbands. This MCINP strategy offers a paradigm to develop next-generation materials for structural applications.