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Interactions between neighboring grains influence the macroscale behavior of polycrystalline materials, particularly their deformation behavior, damage initiation and propagation mechanisms. However, mapping all of the critical material properties normally requires that several independent measurements are performed. Here we report the first grain mapping of a polycrystalline foil using a pixelated energy-dispersive X-ray area detector, simultaneously measuring X-ray fluorescence and diffraction with the Maia detector in order to determine grain orientation and estimate lattice strain. These results demonstrate the potential of the next generation of X-ray area detectors for materials characterization. By scanning the incident X-ray energy we investigate these detectors as a complete solution for simultaneously mapping the crystallographic and chemical properties of the sample. The extension of these techniques to broadband X-ray sources is also discussed. [ABSTRACT FROM AUTHOR]

Abstract: Line profile analysis was carried out on neutron diffraction patterns collected by the energy-dispersive method for an in situ tensile-deformed AISI-316 stainless steel specimen. The experiments were carried out at the VULCAN engineering beam line of the spallation neutron source of the Oak Ridge National Laboratory. Both the dislocation densities and the local stresses in grains oriented with different h k l crystal directions along the tensile axis were determined. The work-hardening equation of Taylor was tested for the h k l-dependent phenomenological constant α. The grain-orientation-dependent α values were directly related to the heterogeneity of dislocation distribution in correlation with previous transmission electron microscopy data. [Copyright &y& Elsevier]