Overview of High-Energy X-Ray Diffraction Microscopy (HEDM) for Mesoscale Material Characterization in Three-Dimensions: By Means of Data Science and Optimal Learning

Abstract

Over the past two decades, several non-destructive techniques have been developed at various light sources for characterizing polycrystalline materials microstructure in three-dimensions (3D) and under various in-situ thermo-mechanical conditions. High-energy X-ray diffraction microscopy (HEDM) is one of the non-destructive techniques that facilitates 3D microstructure measurements at the mesoscale. Mainly, two variations of HEDM techniques are widely used: (1) Near-field (nf) and (2) far-field (ff) which are employed for non-destructive measurements of spatially resolved orientation ($$\sim $$∼1.5 $$\upmu $$μm and 0.01$$^\circ $$∘), grain resolved orientation, and elastic strain tensor ($$\sim $$∼10$$^{-3}$$-3–10$$^{-4}$$-4) from representative volume elements (RVE) with hundreds of bulk grains in the measured microstructure (mm$$^{3}$$3). To date HEDM has been utilized to study variety of material systems under quasi-static conditions, while tracking microstructure evolution. This has revealed new physical mechanisms that were previously not observed through destructive testing and characterization. Furthermore, measured 3D microstructural evolution data obtained from HEDM are valuable for informing, developing, and validating microstructure aware models for accurate material property predictions. A path forward entails utilizing HEDM for initial material characterization for enabling microstructure evolution measurements under dynamic conditions.