Oxygen-mediated high uniform plasticity in α-β titanium alloys

Titanium alloys are critically important materials, yet their development has long been constrained by a fundamental trade-off between yield strength and uniform elongation—a more challenging limitation than the conventional strength–ductility trade-off. Here, we present a dual strategy for α–β titanium alloys that transforms high oxygen from an embrittling liability into a powerful performance enabler. First, we leverage high oxygen (≥0.40%) to activate prominent pyramidal <c + a> slip in the α-phase. Second, we engineer a tailored α–β microstructure through alloy design (Ti–O–Fe), laser-based powder bed fusion, and annealing to enable sustained slip transfer across α–β interfaces. The resulting high-strength α–β alloys achieve record uniform elongations: Ti-0.45O-4Fe delivers ≥14% (total: ≥27%) at yield strengths ≥980 MPa, and Ti-0.5O-5Fe achieves ≥13% (total: ≥23%) at yield strengths ≥1075 MPa. This work simultaneously addresses the yield strength–uniform elongation trade-off and oxygen embrittlement, demonstrating a design paradigm for α–β titanium alloys.