A field ion microscopic and microprobe study was made of (011) twin-related domains in the -phase of an alloy which contained 5at%V. On the basis of geometrical considerations, the formation of an (011) twin boundary was deduced to require that a part of the lattice should undergo a 90 rotation about the <100> axis. Because a rigid rotation was not possible in the lattice, it was suggested that the (011) twin boundary was generated by the impingement of two -TiAl domains which had nucleated independently in one Ti3Al lamella.

Z.G.Liu, J.Wesemann, G.Frommeyer, M.Kreuss: Scripta Metallurgica et Materialia, 1995, 33[4], 627-31