Place: 2018 KIM Fall Conference: Symposium on Microstructure Modeling of Materials, Daejeon, South Korea
Nickel-base superalloys are the material of choice for many high temperature applications due to their exceptional creep resistance at elevated temperatures. This property is strongly connected to their unique microstructure consisting of cuboidal γ’ particles embedded in a γ matrix. Thus, understanding the evolution of this microstructure at elevated temperatures is paramount. A combined approach of phase-field method and phenomenological crystal plasticity is used to investigate creep deformation and its connection to the microstructure. Phase-field model and crystal plasticity model are implemented in the comprehensive OpenPhase library, a multi-phase-field, multi physics library. The phenomenological crystal plasticity model includes a hardening model, which enables the precise simulation of primary and secondary creep. A model for repulsion and coalescence of γ̕ precipitates has been developed, this model ensures realistic raft formation during creep. Microstructure and plastic strain evolution have been benchmarked with experiments.