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

Pile-up interactions in the gamma phase of MC2 nickel-based superalloy have been studied by both atomic force microscopy and transmission electron mic roscopy. The examinations of surface slip-line patterns and the fine struct ure 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 dir ections has been simulated. The critical applied stress required for these pile-ups to cross over in the bulk crystal has been determined in good agre ement with the microscopy observations.