Phase-field modeling of cavity growth and dislocation climb

Abstract

An original phase-field model coupling cavity growth, dislocation climb and vacancy diffusion is proposed. The model naturally accounts for elastic interactions between objects while its kinetic equations guarantee that matter is conserved when bulk vacancies are exchanged at the cavity surface or the dislocation core. An original spectral method that drastically reduces simulation time is also proposed in order to efficiently obtain the stationary vacancy concentration profiles during the objects evolution. It is shown how this model can be calibrated in a physically-informed way to reproduce diffusion-mediated cavity growth and dislocation climb under the so called “local equilibrium assumption”. As an application of the model, the microstructural evolution of an annealed irradiated aluminum sample, implying interactions between several cavities and dislocations, is simulated. Non trivial effects regarding the dislocation-induced elastic interactions on the closure kinetics of cavities are notably highlighted.