Multiscale modelling of the precipitation evolution and strengthening in Al-Cu alloys during the creep aging

During the creep aging forming process, the θ’ are the primary strengthening phases in Al-Cu alloys. In this study, the evolution of precipitates during creep aging and dislocation-precipitate interaction were simulated using phase field methods (PFM) and discrete dislocation dynamics (DDD). The phase transition process from Al-matrix to θ” to θ ‘phase was simulated, and the results were in good agreement with the in-situ results reported. Subsequently, the interaction between dislocations and precipitates was simulated. A modified Orowan model considering orientation distribution with parameters calibrated by dislocation dynamics simulations is suggested in light of these investigations, enabling rapid prediction of precipitation strengthening. This work makes it possible to quantitatively and accurately calculate the precipitation evolution and precipitation strengthening of Al-Cu alloys during creep aging process.