When illuminating a sample with x-rays, a number of interactions occur revealing different physical properties of the sample. Using appropriate detectors suitably arranged around the sample, we propose a novel synchrotron measurement tomographic scheme to map structural, chemical and nanocrystalline details of the inner part of a sample.

Microtomography is a well-established technique to reconstruct the sample internal structure. With the advent of third generation synchrotron sources, high-resolution tomography could be reached that reveals details within a micron. With fluorescence tomography, 3D quantitative chemical imaging is also possible by measuring fluorescent x-rays in a first generation scanner geometry.

We propose here to record a diffraction pattern simultaneously to the fluorescence and transmission signal. It consists in translating the sample in front of a high intensity monochromatic pencil beam. At each point along the linear scan, we record the incoming and outgoing intensities for transmission tomography, a fluorescence spectrum for chemical imaging, and a diffraction pattern for crystalline phase imaging. Then, we rotate the sample and we repeat the process until one turn is achieved. After integration of the images to obtain linear diffraction patterns, region of interest corresponding to each Bragg peaks are selected to generate sinograms. Using a classical algebraic reconstruction technique, we compute an image of the inner distribution of each crystalline phase.

Measurements have been performed at the ESRF beamline ID22. Apart from the validation of the method with phantoms, three examples covering three engineering topics have been tested. High contrast images have been obtained when classical tomography did not work. The method gives a highly suitable combination of chemical and crystalline data and its sensitivity has been proved to be much higher than in classical microdiffraction analysis.

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/11333 must be provided.

1. X-ray and IR micro-analysis studies of bone mineral and related biological samples