DEFORMATION MECHANISMS COUPLED WITH PHASE FIELD AND CRYSTAL PLASTICITY MODELING IN A HIGH TEMPERATURE POLYCRYSTALLINE NI-BASED SUPERALLOY

Physics-based modeling of disk superalloys is inherently complex due to the strong influence of microstructure on properties, as well as the multitude of deformation mechanisms operative at elevated temperatures. The present contribution will focus on the effects of monotonic and cyclic loading conditions, and the underlying deformation mechanisms will be discussed. Detailed substructure analysis of deformed specimens was conducted with scanning transmission electron microscopy diffraction-contrast methods. These characterization efforts have led to a series of phase field simulations in which the interaction of various deformation modes with experimentally measured precipitate configurations can be explored and critical parameters quantified. Additionally, these results have been incorporated into a novel, dislocation-density-based crystal plasticity model that has been calibrated based on a single crystal response, and enables the computationally efficient modeling of polycrystalline behavior.