Modeling Dislocation Dissociation and Cutting of γ′ Precipitates in Ni-Based Superalloys by the Phase Field Method

Abstract

ABSTRACTWe incorporate γ-surface data of both γ and γ′ phases from ab initio calculations into the phase field model to study dislocation dissociation and interaction with γ′ particles in Ni-based superalloys. Through three examples we demonstrate the unique capabilities of the model in characterizing the core structure of a dissociated superdislocation in γ′ phase, the creation and annihilation of planar defects such as CSF and APB caused by dislocation cutting through the γ′ phase and the interplay between the cutting and looping mechanisms.