Dislocation-twin-precipitate synergy imparts 2.3 GPa yield strength and 18.2% ductility in MPEA at 77 K

Achieving an exceptional strength-ductility synergy is essential for cryogenic structural materials. However, ultrahigh-strength alloys frequently suffer from limited ductility, which restricts ductility. In this study, a (CoNiCr)81Fe9Ti5Mo4Al1 multi-principal element alloy (MPEA) was subjected to cold drawing followed by aging to introduce a high density of dislocations, nanotwins, and supranano precipitates. Consequently, the alloy exhibits a high yield strength of 2.3 GPa and an elongation of 18.2% at 77 K. Dislocation tangles and supranano precipitates impart strong dislocation pinning, while nanotwin networks generate pronounced back-stress strengthening. These mechanisms enhance strength-ductility synergy at cryogenic temperatures and offer a viable pathway for designing strong and ductile cryogenic structural alloys.