The structures of  = 5 [001] 36.8,  = 25 [001] 16.26 and  = 3 [011] 109.47 coincidence site lattice tilt boundaries in Ni3(Al0.8Ti0.2) L12 bi-crystals, which had been prepared by hot pressing, were investigated by means of high-resolution transmission electron microscopy and image simulation. The atomic arrangement in the  = 5 [001] 36.8 boundary was asymmetrical, with a small degree of rigid-body translation. The accommodation of atoms was small and was localized on a near grain-boundary plane. The atomic arrangement in the  = 25 [001] 16.26 boundary was asymmetrical, with no appreciable rigid-body translation. Some atoms were withdrawn, and it was interpreted as being an array of dissociated a/2<110> super-partials. The atomic arrangement in the  = 3 [011] 109.47 boundary was mainly symmetrical. The local accommodation of atoms, and the rigid-body translation, varied with the deviation from the grain-boundary plane. Atom-sized cavities were often observed in the present coincidence site lattice boundaries.

High-Resolution Electron Microscopy of Grain Boundaries in Ni3(Al0.8Ti0.2) Bicrystals II. Coincidence Site Lattice Boundaries. Takasugi, T., Emori, H., Hiraga, K.: Philosophical Magazine A, 1997, 75[5], 1417-34