Abstract
During creep at elevated temperatures, the performance of directionally solidified nickel-based superalloys experiences progressive degradation, accompanied by significant microstructure evolution. In this study, creep tests of varying durations were conducted on smooth specimens, revealing typical microstructure evolution, including dissolution, coarsening, and rafting of the γ′ phase. The process of microstructure evolution during creep was precisely quantified utilizing an advanced image processing technique. Subsequently, a phenomenological model was formulated to predict the evolution of the γ/γ′ microstructure. Furthermore, with the introduction of the microstructure evolution model, a multiscale creep constitutive model was established within the framework of crystal plasticity. This model encompasses various dislocation strengthening mechanisms, including dislocation bypassing, dislocation pairs shearing, and dislocation hardening. The constitutive model can accurately describe both the microstructure evolution and creep deformation of the DZ406 superalloy at various temperatures, with maximum errors of 18.13% and 24.31%, respectively. Finally, the model under multiaxial stress conditions was validated through creep tests on specimens with a film-cooling hole. The maximum prediction errors for microstructure evolution and creep life were 30.46% and 28.00%, respectively.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
