Three-dimensional neutron diffraction study of dendrite growth behavior in Ni-based single-crystal turbine blades

Three-dimensional Neutron Diffraction (3DND) microscopy is performed using a monochromatic beam and applied for the first time to investigate the dendrite growth behavior in Ni-based single-crystal turbine blades. Leveraging the high penetration depth and non-destructive characterization capabilities of neutrons, 3DND provides a statistical analysis of crystallographic orientation distributions and stress states of single crystal at component level . In this study, lattice constants of both γ and γ' phases decrease progressively during dendritic growth, with γ phase exhibiting initial tensile strain that subsequently relaxed to zero. Misorientation analysis reveals a tilt misorientation reaching up to 5°, significantly larger than the twist of 1° Both types of misorientation increases as the dendrites develop, highlighting the anisotropic nature of microstructural evolution. These findings demonstrate the potential of 3DND for characterizing internal lattice strain, orientation distributions, and defect evolution in critical structural components, paving the way for improved manufacturing processes and material reliability.