In-situ atomic force microscopy and transmission electron microscopy observations of the deformation of MC2 nickel-based superalloy γ phase

Pile-up interactions in the gamma phase of MC2 nickel-based superalloy have been studied by both atomic force microscopy and transmission electron microscopy. The examinations of surface slip-line patterns and the fine structure of dislocation pile-ups enable a minimum distance between pile-up slip planes to be derived. The behaviour of two pile-ups gliding in opposite directions has been simulated. The critical applied stress required for these pile-ups to cross over in the bulk crystal has been determined in good agreement with the microscopy observations.