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

摘要

We incorporate gamma-surface data of both gamma and gamma' phases from ab initio calculation into the phase field model to study dislocation dissociation and interaction with gamma' 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 gamma' phase,the creation and annihibition of planar defects such as CSF and APB caused by dislocation cutting through the gamma' phase and the interplay between the cutting and looping mechanisms.