Dynamic quantitative deformation mapping of slip activities in NBSC superalloy using sampling moiré method

Quantitative assessment of microscale slip activities and plastic localizations is essential for understanding the complex deformation mechanisms in crystalline materials. However, few experimental studies have been able to dynamically measure the deformation fields of rapidly evolving slip activities at the microscale. In this study, we used the Sampling Moiré Method (SMM) to directly measure the dynamic deformation fields of slip activities in Nickel-Based Single-Crystal (NBSC) superalloy under in-situ tensile test, and the strain and displacement fields under the evolving microplastic events with intense slip activities around the notch of the NBSC superalloy specimen were obtained for the first time. The dynamic evolution of slip bands was quantitatively characterized through detailed statistical analysis of strains and displacements under different loads. The locations of the initial appearance of slip traces were successfully predicted by the regions of plasticity localization. The results show that the deformation fields exhibit both high spatial and temporal resolutions, enabling the capture of nanometer-scale displacement fields and visualization of the dynamic fluidity of slip accumulation. This method demonstrates the superiority of the dynamic characterization of the plastic deformation field at the microscale and the promise of its application for characterizing the slip activities of various crystalline metals.