3 GPa dual-phase stainless steel from synergistic heterogeneous structure and nano-precipitate

Grain refinement is the most common strategy to improve the mechanical performance of metals such as strength, wear resistance and fatigue. For the 2101 duplex stainless steel (DSS), a heterogeneous microstructure composed of sub-25 nm fiber grains and submicron elongated grains was successfully prepared by heavily drawing taking advantage of the heterogeneous microstructural design. The DSS possesses ultra-high strength of 3 GPa which is 15% higher than the reported that of DSS or a leading strength-ductility combination of 1.43 GPa and 17%. This study provides a strategy for heterogeneous microstructural design to achieve excellent mechanical performance, specifically high strength.