Place: Euromat 2015, Warsaw, Poland
Stability of the microstructure at elevated temperatures is the major factor controlling the performance of Ni-base superalloys. At high temperatures rafting and creep phenomena become important. In this study we present a 3-dimentional numerical simulation of γ - γ′ microstructure evolution in Ni-base superalloy during high- temperature creep. We investigate the effects of external loading on the rafts formation with and without considering the creep phenomenon. Classical creep models were incorporated in the Phase-field modeling for precipitates evolution simulation involving creep. In this study we investigate the kinetics of raft formation considering the effect of inelastic strain during high-temperature creep. We also investigate the effect of varying misfit strain on the rafts formation. The results of microstructure evolution and creep rate versus time are compared with experiments.