Deformation-induced dislocation networks at the gamma-gamma' interfaces in the single-crystal superalloy SC16: A mechanism-based analysis

The formation of dislocation networks at the gamma-gamma' interfaces in a single-crystal nickel-based superalloy SC16 has been studied after deformation at 1223 K. The dislocation segments in the networks were characterized. As a result the dislocation substructure was found to be quite different on interfaces parallel and perpendicular to the applied stress direction. Reactions between glide dislocations were essentially observed on the latter type of interface. A model of network formation based on cross-slip leading to dislocation interactions has been proposed to explain the observed networks.