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2.4 Neutron Diffraction Open Research Online The Open University’s repository of research publications and other research outputs Combined Neutron Imaging and Diffraction: Instrumentation and Experimentation Thesis How to cite: Burca, Genoveva (2013). Combined Neutron Imaging and Diffraction: Instrumentation and Experimentation. PhD thesis The Open University. For guidance on citations see FAQs. c 2013 The Author https://creativecommons.org/licenses/by-nc-nd/4.0/ Version: Version of Record Link(s) to article on publisher’s website: http://dx.doi.org/doi:10.21954/ou.ro.0000f116 Copyright and Moral Rights for the articles on this site are retained by the individual authors and/or other copyright owners. For more information on Open Research Online’s data policy on reuse of materials please consult the policies page. oro.open.ac.uk crrei> Combined Neutron Imaging and Diffraction: Instrumentation and Experimentation Thesis submitted to The Open University for the degree of Doctor of Philosophy in the Faculty of Mathematics, Computing and Technology (MCT) By Genoveva Burca Materials Engineering Group The Open University September 2012 ProQuest Number: 13835948 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a com plete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest ProQuest 13835948 Published by ProQuest LLC(2019). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States C ode Microform Edition © ProQuest LLC. ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106- 1346 Abstract A combined neutron imaging and diffraction facility, IMAT (Imaging and Materials Science & Engineering) is developed at ISIS (Target Station 2). One subject of this thesis was focused on the design and optimization of the imaging part of IMAT, using the Monte Carlo calculation software package McStas. Hence, the neutron guide dimensions, the effects of the gaps in the neutron guide on imaging detectors, gravitation effects in the neutron guide and also the influence of the pinhole size on the image were studied. All these investigations were made taking into account the most important design criteria: to maximise the neutron flux, to obtain a good energy resolution whilst retaining a large neutron bandwidth and a long flight path and to minimize the artefacts obtained in the neutron radiographies. After a compromise between imaging, diffraction and engineering requirements had been reached, the results from simulations specific to the current IMAT design were studied: wavelength distribution, beam profiles at different points along the beamline, beam divergence, neutron intensity distribution and flux depending on the pinhole size and the wavelength bands. Moreover, generation of IMAT imaging data with a sample led to full tomographic simulations and modelling wavelength effects. Another objective of the thesis was to study the complementarity between neutron imaging and neutron diffraction experiments. For this, a new instrument control concept that exploits tomography data to guide diffraction experiments on samples with complex structures and shapes named “tomography driven diffraction” (henceforth, TDD) was developed. The method has been proved to be viable using combinations of individual tomography and diffraction instruments: NEUTRA (PSI) and ENGIN-X (ISIS) for different samples drawn from the engineering and heritage sciences. On IMAT it will be possible to perform tomography, mark the measurement points and proceed to the diffraction measurements as one continuous process. Declaration The studies outlined in this thesis were undertaken in the Materials Engineering Group, from The Open University, Milton Keynes, UK and supervised by Dr. Jon James, Prof. Mike Fitzpatrick and Dr. Winfried Kockelmann (ISIS). I declare that all of the work was performed by the author except where otherwise indicated, and this thesis has not been submitted in support of an application for another degree or qualification of this or any other university or other institution of learning. Publications Work included in this dissertation has been presented in the following publications and conference proceedings: Journal papers: Kockelmann W., Zhang S.Y., Kelleher J.F., Nightingale J.B., Burca G., James J.A. (2012). IMAT - a new imaging and diffraction instrument at ISIS. In: Physics Procedia (to appear) Paradowska A.M., Tremsin A., Kelleher J.F., Zhang S.Y., Paddea S., Burca G., James J.A., Ahmed R., Faisal N.H., Grazzi F., Fest G., Andreani C., Civita F., Bouchard P.J., Kockelmann W., Fitzpatrick M.E. (2012). Modern and Historical Engineering Components Investigated by Neutron Diffraction on ENGIN-X. In: Journal of Solid Mechanics and Materials Engineering, vol.6, no.6, p.408-418. Burca G.. James J.A., Kockelmann W., Fitzpatrick M.E., Zhang S.Y., Hovind J., van Langh R. (2011). A new bridge technique for neutron tomography and diffraction experiments. In: Nuclear Instruments and Methods in Physics Research Section A. Accelerators, Spectrometers, Detectors and Associated Equipment, vol. 651, issue 1, p.229-235. Van Langh R., James J.A., Burca G.. Kockelmann W., Zhang S.Y., Lehmann E., Estermann M., Pappot A. (2011). New insights of alloy compositions by studying renaissance bronze statuettes by combined neutron imaging and neutron diffraction techniques. In: Journal of Analytical Atomic Spectrometry, vol.26, nr.5, p.949-958. Conference proceedings: James J.A., Burca G., Kockelmann W. (2009). Image driven diffraction. In: Proceedings of the 2nd Workshop on Neutron Wavelength Dependent Imaging, Abingdon, UK. Zhang S.Y., Kockelmann W., Paradowska A., James J.A., Burca G„ Chapon L. (2009). IMAT: m Imaging and Engineering Facility for ISIS TS-II, 5th International Conference on Mechanical Stress Evaluation by Neutrons and Synchrotron Radiation, Mito, Japan. Burca G„ James J.A., Fitzpatrick M.E., Kockelmann W., Kelleher J.F., Zhang S.Y., Hovind J., van Langh R. (2010). Tomography driven diffraction experiments. In: Proceedings of the 3rd Workshop on Neutron Wavelength Dependent Imaging, Saporo, Japan. Acknowledgments I would like to express my gratitude toward my supervisor Dr. Jon James, for his enthusiastic guidance, his effort, diligence and patience during these years materialised in intellectual assistance and support for my professional growth. I am also very grateful to my co-supervisor, Prof. Mike Fitzpatrick for providing me with the financial support which made my attendance to conferences and trainings possible. Both of them deserve my praise for unreservedly believing in me right from the beginning of my PhD studies. I thank my co-supervisor Dr. Winfried Kockelmann for his suggestions, introducing me into the Rietveld analysis world and remembering me to take a break from time to time. Without all your helpful comments and encouragements I would not have been able to complete this thesis! Thanks are also due to the staff at ENGEN-X instrument, at ISIS, Dr. Anna Paradowska and Dr. Shu-Yan Zhang for their friendship, helpful discussions and support with the diffraction experiments. I also kindly acknowledge Dr. Eberhard Lehmann and Peter Vontobel for valuable discussions during my imaging experiments at the NEUTRA instrument at the PSI. I thank all the staff members of Materials Engineering Group (OU) and all my friends: Sue, David, Foroogh, Yuki, Gabriela, Richard. I thank Courtney for his openness, unreserved willing to help and most of all for his encouraging smile. I would like thank to my wonderful parents, my parents in law, my sister Catalina and her husband for their love and moral support. There is one person without whom this work would never been started, developed or finalised. This thesis is dedicated to you, my beloved husband, Cyprian! v Contents Abstract .....................................................................................................................................i Declaration ............................................................................................................................. iii Publications ............................................................................................................................ iv Acknowledgments .................................................................................................................. v Contents .................................................................................................................................vii List of Figures ........................................................................................................................ xi List of Tables .........................................................................................................................xx 1 Introduction ..........................................................................................................................1 2 Neutron imaging and diffraction - a general overview ..................................................5 2.1 Neutron properties and applications ....................................................................................... 5 2.1.1 Neutron characteristics ......................................................................................................5 2.1.2 Neutrons in material
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