Sub-grain orientation resolution during continuous loading using only far-field HEDM

A far-field data reduction algorithm for high-energy X-ray diffraction microscopy (HEDM) has been adapted to extract sub-grain orientation descriptors in a polycrystalline material during continuous in situ loading experiments. Previously, the standard data reduction algorithm would only extract grain-averaged strains, orientation, and the centroid position. A new descriptor, the grain orientation envelope (GOE), is introduced as a measure of the intragranular microstructure extracted from every grain during a continuous loading experiment. Initial results showing the evolution of a GOE from one grain in the titanium alloy, Ti-7Al, during a tension test is presented as a demonstration of the nature of the data.