Sub-grain scale elastic and plastic deformations in polycrystalline metallic alloys assessed via digital image correlation techniques
Résumé
High resolution scanning electron microscopy (HR-SEM) and laser scanning confocal microscopy (HR-LSCM) digital image correlation (DIC) techniques were investigated for assessing strain distribution within individual grains during deformation in the macroscopic elastic and plastic regime. The anisotropic response of a Ni-based polycrystalline superalloy was experimentally demonstrated at the grain scale. Local plastic strain localization within preferentially oriented grains was documented under loading as low as 80% of the macroscopic yield strength of the material. Intense strains along bands were observed in the macroscopic plastic regime, correlating with {111}[1-10] slip systems.