Dual‐Array Nano Configuration for High‐Performance Metastable β Titanium Alloys

Abstract Catastrophic failures in engineering metallics frequently occur at high temperatures. A fundamental understanding of plastic deformation and the mechanisms governing the strength‐ductility trade‐off is essential for developing titanium alloys exhibiting superior properties at elevated temperatures. Herein, a metastable β titanium alloy (Ti‐15.1Mo‐3.1Nb‐2.77Al‐0.21Si, wt.%) exhibits unexpected mechanical properties, including an ultimate tensile strength of 863 MPa and a total elongation of 78.3% at 500 °C, accompanied by a continuous and strong work hardening rate (2000–3100 MPa). Dislocation slip and heating play pivotal roles in interlaced parallel α nucleation, and thermal activation promotes interlaced α nucleation. Finally, the dual‐array nano configuration of dense (≈68%) and thin (≈10 nm in width) α phase forms. Hierarchical microstructural evolutions, including β to α phase transformation, nano α grains with dual‐array configurations (interleaved and parallel), and dislocation interaction, contribute to the excellent mechanical properties. These findings reveal that dynamic nano α precipitation with unique dual‐array nano configurations can unveil new prospects for the development of high‐performance metastable titanium alloys at elevated temperatures.