Microstructural anisotropy and its influence on the internal stress field within grains: experimental confrontation with full-field crystal plasticity models

Comprehensive microscopic scale studies bring valuable information for extrapolating to themacroscopic mechanical response of materials and they can feed advanced multiscale crystal plasticity models.However, fundamental questions on the representativeness of observed phenomenon must be raised whileextrapolating microstructural observations to the macro-scale. In this framework, macroscopic mechanicaltesting of bulk specimens has been successfully combined with a dislocation-scale characterization technique:Accurate Electron Channeling Contrast Imaging (A-ECCI). In this study, the focus will be on BCC titaniumwhere 48 slip systems are potentially active and pencil glide occurs and hence serves as a challengingbenchmark for the proposed methodology. In this work, fundamentals on the defect contrasts and the experimentprocedure will be presented. Second, the full potentiality of A-ECCI for following the evolution of deformationmicrostructures will be highlighted. Micro-structural information available from ECCI has been used forexamining the effect of anisotropic elastic and plastic properties on the local stress field and dislocation activitydistribution within grains at different stages of deformation and gather statistical information for identifyingrelevant micromechanical and microstructural variables that influence the material behavior.