TY - GEN A1 - Harbich, Karl-Wolfram A1 - Schors, Jörg A1 - Lange, Axel A1 - Hentschel, Manfred P. ED - van Hemelrijck, D. T1 - X-ray refraction - new methods for non-destructive evaluation of advanced materials T2 - 2nd International Conference on Emerging Technologies in NDT CY - Athens, Greece DA - 1999-05-24 KW - X-ray refraction PY - 2000 SN - 90-5809-127-9 SP - 207 EP - 212 PB - Balkema CY - Rotterdam AN - OPUS4-851 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Harbich, Karl-Wolfram A1 - Hentschel, Manfred P. T1 - Nondestructive Characterization of Monolithic Ceramics by X-Ray Refraction T2 - 7th Euro Ceramics - Conference and Exhibition of the European Ceramic Society (ECerS) CY - Brugge, Belgium DA - 2001-09-09 KW - X-ray refraction KW - Non-destructive testing KW - Porosity KW - Specific surface KW - Pore size PY - 2001 SN - 1013-9826 VL - 206-213 SP - 673 EP - 676 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-1861 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Bernd R. A1 - Hentschel, Manfred P. A1 - Harbich, Karl-Wolfram A1 - Lange, Axel A1 - Schors, Jörg T1 - X-ray refraction topography for non-destructive evaluation of advanced materials T2 - 15th World Conference on Non-Destructive Testing (WCNDT) CY - Roma, Italy DA - 2000-10-15 KW - X-ray refraction PY - 2000 UR - http://www.ndt.net/article/wcndt00/papers/idn257/idn257.htm SN - 1435-4934 VL - 5 IS - 11 SP - 1 EP - 7(?) PB - NDT.net CY - Kirchwald AN - OPUS4-871 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Müller, Bernd R. A1 - Lange, Axel A1 - Harwardt, Michael A1 - Hentschel, Manfred P. A1 - Illerhaus, Bernhard A1 - Goebbels, Jürgen A1 - Bamberg, J. A1 - Heutling, F. T1 - Micro Crack Characterization of Metal Matrix Composites by 3D-Refraction-Computed-Tomography T2 - 16th World Conference on Nondestructive Testing CY - Montreal, Canada DA - 2004-08-30 KW - NDE KW - X-ray refraction KW - Composites KW - MMC PY - 2004 SP - 9 pages PB - International Committee for Non-Destructive Testing CY - Montreal AN - OPUS4-5486 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Müller, Bernd R. A1 - Hentschel, Manfred P. ED - Czichos, Horst T1 - Micro-diagnostics: X-ray and synchrotron techniques N2 - Beyond classical X-ray techniques are used for the purpose of preferably short-term applications, but some supplementary X-ray and synchrotron techniques for higher resolution microdiagnostics take advantage of scattering effects. In contrast to directly imaging methods their resolution is only limited by the diffraction limit of the X-ray wavelength, far below the atomic dimensions. These techniques of scanning topography and refraction synchrotron tomography may permit the systematic diagnostics for finding and exploiting structure/property relations like correlations among atomic, nano and microstructures with macroscopic properties. Their basic advantage over microscopic techniques is their potential for the non-destructive characterisation of materials, far from invasive sample treatments. They combine scattering and spatial resolution. KW - X-ray KW - X-ray refraction KW - X-ray refraction topography KW - X-ray refraction tomography KW - X-ray scattering KW - USAXS KW - Wide angle X-ray scattering KW - WAXS KW - Interfaces KW - Inner surface density KW - Diffraction enhanced imaging KW - DEI KW - Synchrotron radiation KW - Synchrotron refraction computed tomography KW - SRCT KW - Fibre orientation KW - X-ray diffraction microscopy PY - 2013 SN - 978-3-642-25849-7 SN - 978-3-642-25850-3 U6 - https://doi.org/10.1007/978-3-642-25850-3_14 IS - Chapter 14 SP - 287 EP - 300 PB - Springer CY - Berlin Heidelberg AN - OPUS4-27746 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rack, A. A1 - Zabler, S. A1 - Müller, Bernd R. A1 - Riesemeier, Heinrich A1 - Weidemann, Gerd A1 - Lange, Axel A1 - Goebbels, Jürgen A1 - Hentschel, Manfred P. A1 - Görner, Wolf T1 - High resolution synchrotron-based radiography and tomography using hard X-rays at the BAMline (BESSY II) N2 - The use of high brilliance and partial coherent synchrotron light for radiography and computed tomography (CT) allows to image micro-structured, multi-component specimens with different contrast modes and resolutions up to submicrometer range. This is of high interest for materials research, life science and non-destructive evaluation applications. An imaging setup for microtomography and radiography installed at BESSY II (a third generation synchrotron light source located in Berlin, Germany) as part of its first hard X-ray beamline (BAMline) can now be used for absorption, refraction as well as phase contrast — dedicated to inhouse research and applications by external users. Monochromatic synchrotron light between 6 keV and 80 keV is attained via a fully automated double multilayer monochromator. For imaging applications the synchrotron beam transmitted by the sample is converted with a scintillator into visible light. By use of microscope optics this luminescence image is then projected onto, e.g., a CCD chip. Several scintillating materials are used in order to optimise the performance of the detector system. Different optical systems are available for imaging ranging from a larger field of view and moderate resolutions (macroscope — up to 14 mm x 14 mm field of view) to high resolution (microscope — down to 0.35 μm pixel size), offering magnifications from 1.8× to 40×. Additionally asymmetric cut Bragg crystals in front of the scintillator can be used for a further magnification in one dimension by a factor of about 20. Slow and fast cameras are available, with up to 16 bit dynamic range. We show the suitability of the setup for numerous applications from materials research and life science. KW - Microtomography KW - Non-destructive evaluation KW - Synchrotron instrumentation KW - Coherent imaging KW - X-ray refraction KW - Phase contrast KW - Holotomography KW - Synchrotron-CT KW - Scintillator KW - Bragg magnification PY - 2008 U6 - https://doi.org/10.1016/j.nima.2007.11.020 SN - 0168-9002 SN - 0167-5087 VL - 586 IS - 2 SP - 327 EP - 344 PB - North-Holland CY - Amsterdam AN - OPUS4-17738 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Bernd R. A1 - Lange, Axel A1 - Harwardt, Michael A1 - Hentschel, Manfred P. A1 - Illerhaus, Bernhard A1 - Goebbels, Jürgen T1 - Synchrotron Refraction CT and Synchrotron Bragg Magnification CT for NDE N2 - X-ray refraction topography techniques are based on ultra-small angle scattering by micro-structural elements causing phase-related effects such as refraction and total reflection at a few minutes of arc as the refractive index of X-rays is nearly unity. The refraction contrast is several times higher than “true absorption” and results in images of cracks, pores and fibre debonding separations below the spatial resolution of the detector. In most cases the investigated inner surface and interface structures correlate to mechanical properties. For the exploration of micro structured materials the refraction technique has been improved by a 3D Synchrotron Refraction Computed Tomography test station. The specimen is placed in an X-ray beam between two single crystals, which suppresses all sample scattering. In addition, an asymmetric cut second crystal can magnify the image up to 50 times revealing nano meter resolution. The technique is an alternative to other attempts on raising the spatial resolution of CT machines. KW - X-ray refraction KW - Diffraction Enhanced Imaging (DEI) KW - Bragg magnification KW - Synchrotron radiation KW - Computed Tomography (CT) KW - Metal Matrix Composites (MMC) KW - Lightweight materials KW - Aerospace PY - 2008 U6 - https://doi.org/10.1784/insi.2008.50.6.316 SN - 0007-1137 VL - 50 IS - 6 SP - 316 EP - 319 PB - British Institute of Non-Destructive Testing CY - Northampton AN - OPUS4-18001 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Bernd R. A1 - Lange, Axel A1 - Harwardt, Michael A1 - Hentschel, Manfred P. A1 - Illerhaus, Bernhard A1 - Goebbels, Jürgen A1 - Bamberg, J. A1 - Heutling, F. T1 - Refraction computed tomography - Application to metal matrix composites N2 - Erstmals wurden MMCs mit Hilfe der Interface-Kontrast verstärkenden Röntgen-Refraktions-Technik in Kombination mit der 3D-CT-Technik untersucht. Die Methode der Röntgen-Refraktions-Topography sowie der Röntgen-Refraktions-Tomography wurden in den letzten Jahren speziell für die zerstörungsfreie Charakterisierung von Leichtbau-Hochleistungs-Werkstoffen wie Verbund-Werkstoffen und Keramiken entwickelt. Die Technik basiert auf der Refraktion von Röntgenlicht an Grenzflächen zwischen Bereichen unterschiedlicher Elektronendichte wie z.B. Faser- und Matrix-Werkstoff. Auf Grund der kurzen Röntgen-Wellenlänge hat der Brechungsindex einen Wert dicht bei eins, sodass der Streuwinkel nur wenige Bogenminuten beträgt. Der Vorteil der kurzen Wellenlänge besteht jedoch darin, dass Poren und Risse detektiert werden können, deren Größe im Nanometerbereich liegen. Damit kann die Refraktions-Technik zum besseren Verständnis von Mikro- und Submikro-Strukturen in der Materialwissenschaft eingesetzt werden. Mit der hier vorgestellten Refraktions-CT wurden Ermüdungsmechanismen an MMCs, bestehend aus SiC-Faser verstärktem Titan (Ti6242) untersucht. Die Messungen wurden am Röntgen-Messplatz der BAM (BAMline) am Synchrotron-Speicherring-BESSY in Berlin Adlershof durchgeführt. KW - X-ray refraction KW - Computed tomography PY - 2004 U6 - https://doi.org/10.3139/120.100592 SN - 0025-5300 VL - 46 IS - 6 SP - 314 EP - 319 PB - Carl Hanser Verlag CY - München AN - OPUS4-5870 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de Andrade Silva, F. A1 - Williams, J. J. A1 - Müller, Bernd R. A1 - Hentschel, Manfred P. A1 - Portella, Pedro Dolabella A1 - Chawla, N. T1 - Three-dimensional microstructure visualization of porosity and Fe-rich inclusions in SiC particle-reinforced Al alloy matrix composites by X-ray synchrotron tomography N2 - Microstructural aspects of composites such as reinforcement particle size, shape, and distribution play important roles in deformation behavior. In addition, Fe-rich inclusions and porosity also influence the behavior of these composites, particularly under fatigue loading. Three-dimensional (3-D) visualization of porosity and Fe-rich inclusions in three dimensions is critical to a thorough understanding of fatigue resistance of metal matrix composites (MMCs), because cracks often initiate at these defects. In this article, we have used X-ray synchrotron tomography to visualize and quantify the morphology and size distribution of pores and Fe-rich inclusions in a SiC particle-reinforced 2080 Al alloy composite. The 3-D data sets were also used to predict and understand the influence of defects on the deformation behavior by 3-D finite element modeling. KW - Synchrotron radiation KW - X-ray tomography KW - X-ray refraction KW - Analyser based imaging KW - Metal matrix composite (MMC) KW - Fatigue PY - 2010 U6 - https://doi.org/10.1007/s11661-010-0260-0 SN - 1073-5623 SN - 1543-1940 VL - 41 IS - 8 SP - 2121 EP - 2128 PB - The Minerals, Metals and Materials Society CY - Warrendale AN - OPUS4-21629 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lange, Axel A1 - Kupsch, Andreas A1 - Müller, Bernd R. A1 - Hentschel, Manfred P. T1 - Edge artefacts of radiographic images by X-ray refraction N2 - The relevance of nano sized structures and interfaces in upcoming technologies requires new non-destructive Xray techniques exploiting attenuation as well as scattering. In the course of driving the resolution and the contrast of modern radiography into micro and nano metre dimension the inevitable scattering effects require increased attention. Several radiologists interpret the observed edge artefacts simply by 'phase contrast' due to different X-ray path lengths within the sample and others refer to Fresnel scattering. The ultra small angle scattering is of high intensity and may reach the level of the primary beam. We present monochromatic synchrotron measurements on rather simply shaped objects (such as plates and cylinders) which prove clearly the dominance of refraction intensity over total reflection and coherent small angle scattering. The refraction conditions hold for angles of incidence of several degrees to the surface, but typical deflection angles range from several seconds to minutes of arc. Additionally to the concept of 'phase contrast' of the primary beam its deflection becomes the essential issue. The appropriate removal of the attenuation contribution enables the imaging of inner surfaces and interfaces by refraction scanning topography. The presented measurements of reference particles demonstrate the reliability of laboratory refraction scanners applying X-ray tubes. T2 - 18th WCNDT - World conference on nondestructive testing CY - Durban, South Africa DA - 2012-04-16 KW - X-ray refraction KW - Small angle scattering KW - Phase contrast radiography KW - Refraction topography KW - Nanostructures KW - Nanocracks PY - 2012 UR - http://www.ndt.net/article/wcndt2012/papers/274_wcndtfinal00274.pdf SN - 978-0-620-52872-6 SP - 1 EP - 11(?) AN - OPUS4-25836 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -