Strain tensor evaluation in polycrystalline materials by scanning high-energy X-ray diffraction

The geometry of high-energy X-ray diffraction setups using an area detector and a rotation axis is analysed. The present paper (part 1) describes the methodology for determining continuously varying spatial distortions and tilt of the area detector based on the reference diffraction rings of a certified powder. Analytical expressions describing the degeneration of Debye rings into ellipses are presented and a robust calibration procedure is introduced. It is emphasized that accurate detector calibration requires the introduction of spatial distortion into the equation describing the tilt. The method is applied to data sets measured at the Advanced Photon Source and at the European Synchrotron Radiation Facility using detectors with different physical characteristics, the GE 41RT flat-panel and the FReLoN4M detector, respectively. The spatial distortion of the detectors is compared with regard to their use in structural and strain tensor analysis, a subject treated in part 2 of the calibration work [Borbély, Renversade & Kenesei (2014).J. Appl. Cryst.Submitted].

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Focusing Optics for High-Energy X-ray Diffraction

Journal of Synchrotron Radiation ◽

10.1107/s0909049598001393 ◽

1998 ◽

Vol 5 (3) ◽

pp. 226-231 ◽

Cited By ~ 35

Author(s):

U. Lienert ◽

C. Schulze ◽

V. Honkimäki ◽

Th. Tschentscher ◽

S. Garbe ◽

...

Keyword(s):

Synchrotron Radiation ◽

High Spatial Resolution ◽

Dispersion Compensation ◽

High Energy ◽

Polycrystalline Materials ◽

X Ray Diffraction ◽

X Ray ◽

Momentum Resolution ◽

Potential Applications ◽

Band Pass

Novel focusing optical devices have been developed for synchrotron radiation in the energy range 40–100 keV. Firstly, a narrow-band-pass focusing energy-tuneable fixed-exit monochromator was constructed by combining meridionally bent Laue and Bragg crystals. Dispersion compensation was applied to retain the high momentum resolution despite the beam divergence caused by the focusing. Next, microfocusing was achieved by a bent multilayer arranged behind the crystal monochromator and alternatively by a bent Laue crystal. A 1.2 µm-high line focus was obtained at 90 keV. The properties of the different set-ups are described and potential applications are discussed. First experiments were performed, investigating with high spatial resolution the residual strain gradients in layered polycrystalline materials. The results underline that focused high-energy synchrotron radiation can provide unique information on the mesoscopic scale to the materials scientist, complementary to existing techniques based on conventional X-ray sources, neutron scattering or electron microscopy.

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On the calibration of high-energy X-ray diffraction setups. II. Assessing the rotation axis and residual strains

Journal of Applied Crystallography ◽

10.1107/s1600576714014290 ◽

2014 ◽

Vol 47 (5) ◽

pp. 1585-1595 ◽

Cited By ~ 4

Author(s):

Andras Borbély ◽

Loïc Renversade ◽

Peter Kenesei

Keyword(s):

Residual Strain ◽

Rotation Axis ◽

Strain Tensor ◽

High Energy ◽

Laboratory Frame ◽

X Ray Diffraction ◽

X Ray ◽

Cell Parameters ◽

Area Detector ◽

Residual Strains

The calibration of high-energy X-ray diffraction setups using an area detector and a rotation axis is discussed. The characterization of the tilt and spatial distortions of an area detector was discussed in part one of this series [Borbély, Renversade, Kenesei & Wright (2014).J. Appl. Cryst.47, 1042–1053]. Part II links the detector frame to the laboratory frame comprising an additional rotation axis and introduces a general diffractometer equation accounting for all sources of misalignment. Additionally, an independent high-accuracy method for the evaluation of the crystallographic orientation and cell parameters of the undeformed reference crystal is presented. Setup misalignments are mainly described in terms of a residual strain tensor, considered as a quality label of the diffractometer. The method is exemplified using data sets acquired at beamlines ID11 (European Synchrotron Radiation Facility) and 1-ID (Advanced Photon Source) on Al and W single crystals, respectively. The results show that the residual strain tensor is mainly determined by the detector spatial distortion, and values as small as 1–2 × 10−4can be practically achieved.

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Three-Dimensional X-Ray Diffraction Microscopy Using High-Energy X-Rays

MRS Bulletin ◽

10.1557/mrs2004.54 ◽

2004 ◽

Vol 29 (3) ◽

pp. 166-169 ◽

Cited By ~ 22

Author(s):

Henning F. Poulsen ◽

Dorte Juul Jensen ◽

Gavin B.M. Vaughan

Keyword(s):

Materials Science ◽

Three Dimensional ◽

High Energy ◽

Polycrystalline Materials ◽

X Rays ◽

X Ray Diffraction ◽

X Ray ◽

Reconstruction Methods ◽

The Individual ◽

Individual Grains

AbstractThree-dimensional x-ray diffraction (3DXRD) microscopy is a tool for fast and nondestructive characterization of the individual grains, subgrains, and domains inside bulk materials. The method is based on diffraction with very penetrating hard x-rays (E ≥ 50 keV), enabling 3D studies of millimeter-to-centimeter-thick specimens.The position, volume, orientation, and elastic and plastic strain can be derived for hundreds of grains simultaneously. Furthermore, by applying novel reconstruction methods, 3D maps of the grain boundaries can be generated. The 3DXRD microscope in use at the European Synchrotron Radiation Facility in Grenoble, France, has a spatial resolution of ∼5 μm and can detect grains as small as 150 nm. The technique enables, for the first time, dynamic studies of the individual grains within polycrystalline materials. In this article, some fundamental materials science applications of 3DXRD are reviewed: studies of nucleation and growth kinetics during recrystallization, recovery, and phase transformations, as well as studies of polycrystal deformation.

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Evolution of Solid-State Microstructures in Polycrystalline Materials: Application of High-Energy X-Ray Diffraction to Kinetic and Phase Evolution Studies

X-Rays and Materials ◽

10.1002/9781118562888.ch5 ◽

2013 ◽

pp. 181-219

Author(s):

Elisabeth Aeby-Gautier ◽

Guillaume Geandier ◽

Moukrane Dehmas ◽

Fabien Bruneseaux ◽

Adeline Beneteau ◽

...

Keyword(s):

Solid State ◽

Phase Evolution ◽

High Energy ◽

Polycrystalline Materials ◽

X Ray Diffraction ◽

X Ray

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Study of Mechanical Behaviour of Polycrystalline Materials at the Mesoscale Using High Energy X-Ray Diffraction

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.996.118 ◽

2014 ◽

Vol 996 ◽

pp. 118-123 ◽

Cited By ~ 1

Author(s):

Andrzej Baczmański ◽

Elżbieta Gadalińska ◽

Sebastian Wroński ◽

Chedly Braham ◽

Wilfrid Seiler ◽

...

Keyword(s):

Mechanical Behaviour ◽

Pearlitic Steel ◽

Tensile Tests ◽

High Energy ◽

Polycrystalline Materials ◽

X Ray Diffraction ◽

Elastoplastic Model ◽

Synchrotron Diffraction ◽

X Ray

Owing to its selectivity, diffraction is a powerful tool for analysing the mechanical behaviour of polycrystalline materials at the mesoscale, i.e. phase and grain scale. In situ synchrotron diffraction (transmission mode) during tensile tests and modified self-consistent elastoplastic model were used to study elastic and plastic phenomena occurring in polycrystalline specimens during deformation. The evolution of stress for grains which belong to different phases of duplex stainless steel and pearlitic steel was analyzed.

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Use of Image-Processing Tools for Texture Analysis of High-Energy X-ray Synchrotron Data

Journal of Applied Crystallography ◽

10.1107/s0021889897016439 ◽

1998 ◽

Vol 31 (5) ◽

pp. 647-653 ◽

Cited By ~ 6

Author(s):

R. Fisker ◽

H. F. Poulsen ◽

J. Schou ◽

J. M. Carstensen ◽

S. Garbe

Keyword(s):

Image Processing ◽

Nonlinear Least Squares ◽

High Energy ◽

Three Dimensions ◽

Polycrystalline Materials ◽

Data Sets ◽

Two Dimensional ◽

X Ray Diffraction ◽

X Ray

The introduction of synchrotron beamlines for high-energy X-ray diffraction raises new possibilities for texture determination of polycrystalline materials. The local texture can be mapped out in three dimensions and texture developments can be studiedin situin complicated environments. However, it is found that a full alignment of the two-dimensional detector used in many cases is impractical and that data-sets are often partially subject to geometric restrictions. Estimating the parameters of the traces of the Debye–Scherrer cones on the detector therefore becomes a concern. Moreover, the background may vary substantially on a local scale as a result of inhomogeneities in the sample environmentetc. A set of image-processing tools has been employed to overcome these complications. An automatic procedure for estimating the parameters of the traces (taken as ellipses) is described, based on a combination of a circular Hough transform and nonlinear least-squares fitting. Using the estimated ellipses the background is subtracted and the intensity along the Debye–Scherrer cones is integrated by a combined fit of the local diffraction pattern. The corresponding algorithms are presented together with the necessary coordinate transform for pole-figure determination. The image-processing tools may be useful for the analysis of noisy or partial powder diffraction data-sets in general, provided flat two-dimensional detectors are used.

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Characterizations of Synthetic 8mol% YSZ with Comparison to 3mol %YSZ for HT-SOFC

Engineering and Technology Journal ◽

10.30684/etj.v38i4a.351 ◽

2020 ◽

Vol 38 (4A) ◽

pp. 491-500

Author(s):

Abeer F. Al-Attar ◽

Saad B. H. Farid ◽

Fadhil A. Hashim

Keyword(s):

Ionic Conductivity ◽

Electrochemical Impedance ◽

Structural Information ◽

Impedance Analysis ◽

High Energy ◽

Yttria Stabilized Zirconia ◽

X Ray Diffraction ◽

Stabilized Zirconia ◽

Powder Morphology ◽

X Ray

In this work, Yttria (Y2O3) was successfully doped into tetragonal 3mol% yttria stabilized Zirconia (3YSZ) by high energy-mechanical milling to synthesize 8mol% yttria stabilized Zirconia (8YSZ) used as an electrolyte for high temperature solid oxide fuel cells (HT-SOFC). This work aims to evaluate the densification and ionic conductivity of the sintered electrolytes at 1650°C. The bulk density was measured according to ASTM C373-17. The powder morphology and the microstructure of the sintered electrolytes were analyzed via Field Emission Scanning Electron Microscopy (FESEM). The chemical analysis was obtained with Energy-dispersive X-ray spectroscopy (EDS). Also, X-ray diffraction (XRD) was used to obtain structural information of the starting materials and the sintered electrolytes. The ionic conductivity was obtained through electrochemical impedance spectroscopy (EIS) in the air as a function of temperatures at a frequency range of 100(mHz)-100(kHz). It is found that the 3YSZ has a higher density than the 8YSZ. The impedance analysis showed that the ionic conductivity of the prepared 8YSZ at 800°C is0.906 (S.cm) and it was 0.214(S.cm) of the 3YSZ. Besides, 8YSZ has a lower activation energy 0.774(eV) than that of the 3YSZ 0.901(eV). Thus, the prepared 8YSZ can be nominated as an electrolyte for the HT-SOFC.

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