A superelastic titanium alloy showing nearly temperature-independent high strength and elastic modulus

Lightweight superelastic alloys with temperature-insensitive properties are critical for deep-space exploration devices, yet their development is hindered by the challenge of simultaneously balancing strength, recoverable strain, and temperature sensitivity. Here, we overcome these limitations in a Ti_50.5Zr₄₀Nb₆Sn₂O_1.5 alloy through Zr/O co-doping to induce local chemical orders (LCOs). This strategy yields an unprecedented combination of large recovery strain (ε_r > 4.5%), high superelastic stress (σ_c > 700 MPa), nearly temperature-independent strength (dσ_c/dT ≈ 0.59 MPa·K⁻¹), and stable elastic modulus over a wide temperature range from 123 K to 298 K. These properties arise from the elastic confinement imposed on the transformable matrix induced by the LCOs, which enhances resistance to dislocation slip and suppresses martensitic transformation, while the modulus hardening caused by LCOs due to anharmonic atomic vibrations compensates for matrix softening. This work provides a feasible and effective route for developing high-performance superelastic alloys with wide-temperature stability through LCO engineering.