Fig. 3. The DPHS nanostructure is stabilized thermodynamically and kinetically.

a IPF maps of the Ti6Al4V5Cu sample annealed at various temperatures, only the IPF maps of α phase is shown for brevity, compressive direction (CD) is denoted in the figure. b High-resolution TEM observation showing a low misfit orientation relationship of α/Ti₂Cu/β phases. c Interfacial structural models for first principles calculations. d Pole figures of the Ti6Al4V5Cu sample annealed at 973 K, the initial low-energy orientation relationship was retained. e Atom probe tomography (APT) analysis in the as-prepared Ti6Al4V5Cu sample, the copper concentration gradient indicating that the Ti₂Cu/β shell can be formed rapidly. f APT analysis of the 923 K/1 h annealed Ti6Al4V5Cu sample. Error bars in e and f indicate standard deviations of measured Al, V, Cu contents.