High-Resolution Neutron Diffraction Setting for Studies of Macro- and Microstrains in Polycrystalline Materials

High-Resolution Neutron Diffraction Setting for Studies of Macro- and Microstrains in Polycrystalline Materials

P. Mikula, M. Rogante, J. Šaroun, M. Vrána

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Abstract. On the basis of our previous experience [1-4], a unique three axis high-resolution experimental setting for nondestructive strain measurements which is based on neutron Bragg diffraction optics with cylindrically bent perfect crystals is presented. The use of focusing in real and namely, in momentum space, from FWHM of diffraction lines the three axis setting provides the d/d resolution (d-lattice spacing) of about 4×10-3 for bulk samples. It permits studies not only macrostrain components resulting from angular shifts of diffraction peaks but also estimations of microstrains in a plastically deformation region by means of profile-broadening analysis. The feasibility of the experimental setting is demonstrated on low carbon steel shear deformed steel wires.

Neutron Diffraction, Bent Perfect Crystals, Bragg Diffraction Optics, Polycrystals, Strains

Published online 9/11/2018, 6 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: P. Mikula, M. Rogante, J. Šaroun, M. Vrána, ‘High-Resolution Neutron Diffraction Setting for Studies of Macro- and Microstrains in Polycrystalline Materials’, Materials Research Proceedings, Vol. 6, pp 63-68, 2018

DOI: http://dx.doi.org/10.21741/9781945291890-11

The article was published as article 11 of the book Residual Stresses 2018

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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