Investigations of hydrogen-promoted α2-lamella decomposition of a γ-TiAl based alloy.

The effect of hydrogen on α 2 -lamella decomposition of a Ti–46Al–2V–1Cr–0.3Ni alloy (at%) was investigated. The extent of α 2 -lamella decomposition was enhanced due to hydrogen addition, which was partly attributed to hydrogen-promoted α 2 →B2 phase transformation and α 2 -phase lamellae coarsening. When the deformation temperature rose to 1473 K, hydrogen-promoted γ-phase twinning and α 2 -phase dislocation movement played a positive role in α 2 -lamella decomposition. [ABSTRACT FROM AUTHOR]