Unprecedented ω single-phase nanocrystalline Ti-Fe alloy prepared by laser-inert gas condensation

Highlights: • An unprecedented ω single-phase structure was obtained in nanocrystalline Ti-Fe. • ω → α phase transformation is activated at 290 °C. • An orientation relationship establishes between ω and α phases: [0001]_ω // [11$\overline{2}$0]_α and (2$\overline{1}\overline{1}$0)_ω // (0001)_α. By using the laser-inert gas condensation (laser-IGC) method, an ω single-phase nanocrystalline (NC) Ti-Fe alloy was prepared for the first time. After annealing at 300 °C for 1 h, ω + α dual-phase structure was obtained via the ω → α phase transition, while an α single-phase structure was achieved when annealed at 350 °C for 1 h. The formation and decomposition of ω-phase were discussed. This work pushed the limit of ω-phase content in NC Ti alloy to 100% and provided scientific insights in tailoring the phases from an ω single-phase structure.