  In this paper, we present a phase field model for the self-climb motion of
prismatic dislocation loops via vacancy pipe diffusion driven by elastic
interactions. This conserved dynamics model is developed under the framework of
the Cahn-Hilliard equation with incorporation of the climb force on
dislocations, and is based on the dislocation self-climb velocity formulation
established in Ref.[1]. The phase field model has the advantage of being able
to handle the topological and geometrical changes automatically during the
simulations. Asymptotic analysis shows that the proposed phase field model
gives the dislocation self-climb velocity accurately in the sharp interface
limit. Numerical simulations of evolution, translation, coalescence and
repelling of prismatic loops by self-climb show excellent agreement with
discrete dislocation dynamics simulation results and the experimental
observation.

Materials Science