Recent developments in synchrotron X-ray diffraction imaging

X-ray diffraction contrast tomography [1] is a near-field X-ray diffraction imaging technique enabling simultaneous characterization of (i) microstructural detail visible in absorption contrast (i.e. second phases, porosity, etc…), and (ii) the crystallographic grain microstructure, revealed through analysis of the Bragg diffraction signals. The non-destructive nature of this technique allows for time-resolved 3D microstructural/crystallographic investigations. With the recent upgrade to a six-dimensional reconstruction framework [2] the method now provides access to spatially resolved crystal orientation maps with an orientation resolution comparable to EBSD and a spatial resolution consistent with the voxel size of the high resolution X-ray imaging detectors. Moreover, like modern electron microscopes, state of the art X-ray diffraction imaging instruments can nowadays offer complementary imaging modalities like phase contrast tomography, X-ray topography [3] and dark-field microscopy [4], the latter two enabling “zoom-in” observations of individual grains at higher spatial resolution. Various examples, illustrating the possibilities and limitations of the outlined multimodal characterization approach for time-lapse observations of plastic deformation, fatigue damage and grain growth will be discussed. References [1] W. Ludwig, P. Reischig, A. King, M. Herbig, E. M. Lauridsen, G. Johnson, T. J. Marrow, J.Y. Buffière, Rev. Sci. Instr. 80, 033905 (2009) [2] N. Vigano, A. Tanguy, S. Hallais, A. Dimanov, M. Bornert, K.J. Batenburg and W. Ludwig, Scientific Reports, 6 (2016) [3] W. Ludwig, E. M. Lauridsen, S. Schmidt, H. F. Poulsen, and J. Baruchel, J. Appl. Crystallogr., 40, 905–911 (2007) [4] H. Simons, A. King, W. Ludwig, C. Detlefs, W. Pantleon, S. Schmidt, I. Snigireva, A. Snigirev, H. F. Poulsen, Nat Communications, 6 (2015)