Equiaxed ultrafine duplex alloys γ-TiAl and α2-Ti3Al are prepared by high-energy milling and hot pressing sintering. Microstructures presenting in the mixed and sintered powders are studied by scanning electron microscopy. Structural characteristics are investigated by high-resolution electron microscopy before and after compression at 1100–1200°C. The data reveal grain sizes of 300–500 and ∼100 nm for sintered γ-TiAl and α2-Ti3Al alloys, respectively. High deformation temperatures and low strain rates lead to low peak flow stress, and at such conditions the α2/γ and α2/α2 interfaces are prone to forming dislocation structure. The studies also reveal the presence of large-angle grain boundaries for the and (0002)α2/(0002)α2 interfaces.
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and (0002)α2/(0002)α2 interfaces.