Pile-up interactions in the γ-phase of the Ni-based superalloy were studied by means of atomic force microscopy and transmission electron microscopy. Examination of the surface slip-line patterns and the fine structures of dislocation pile-ups permitted a minimum distance between pile-up slip-planes to be derived. The behavior of 2 pile-ups, gliding in opposite directions, was simulated. The critical applied stress which was necessary for these pile-ups to cross in the bulk crystal was found to be in good agreement with microscopic observations.

In situ Atomic Force Microscopy and Transmission Electron Microscopy Observations of the Deformation of MC2 Nickel-Based Superalloy γ Phase. C.Coupeau, S.Brochard, M.Jouiad, A.Coujou, J.Grilhé: Philosophical Magazine A, 1999, 79[3], 627-38