Evolution of dislocation microstructure in irradiated Zr alloys determined by X-ray peak profile analysis

During neutron irradiation of metals, owing to the enhanced number of vacancies and interstitial atoms, the climb motion of dislocations becomes significant at room temperature, leading to a recrystallization of the material. Moreover, the vacancies and interstitial atoms tend to form prismatic dislocation loops that play a crucial role in the plastic properties of the materials. X-ray peak profile analysis is an efficient nondestructive method to determine the properties of dislocation microstructure. In the first half of this article, the foundation of the asymptotic peak broadening theory and the related restricted-moments peak-evaluation method is summarized. After this, the microstructural parameters obtained by X-ray peak profile analysis are reported for irradiated E110 and E110G Zr alloys used as cladding material in the nuclear industry.

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X-ray peak profile analysis of CoAl2O4 nanoparticles by Williamson-Hall and size-strain plot methods

Modern Electronic Materials ◽

10.3897/j.moem.4.1.33272 ◽

2018 ◽

Vol 4 (1) ◽

pp. 31-40 ◽

Cited By ~ 2

Author(s):

H. Irfan ◽

K Mohamed Racik ◽

S. Anand

Keyword(s):

Profile Analysis ◽

Spinel Phase ◽

Sol Gel ◽

Chelating Agent ◽

Cubic Phase ◽

Physical Parameters ◽

Deformation Model ◽

Uniform Deformation ◽

X Ray ◽

Peak Broadening

CoAl2O4nanoparticles were prepared by a sol-gel process using citric acid as chelating agent with different calcination temperatures of 600 to 900 °C. The crystalline spinel cubic phase was confirmed by X-ray diffraction results. High-resolution scanning electron microscopy (HRSEM) revealed that nanoparticles of CoAl2O4morphology showed spherical forms with a certain degree of agglomeration. The Williamson-Hall (W-H) method and size-strain method to evaluate the size of crystallites and strain in the CoAl2O4nanoparticles peak broadening were applied. Physical parameters such as strain and stress values were calculated for all XRD reflection peaks corresponding to the cubic spinel phase of CoAl2O4in the range of 20 to 70° from the modified plot shape by W-H plot assuming a uniform deformation model (UDM), uniform stress deformation model (USDM), uniform deformation energy density model (UDEDM) and by the size-strain plot method (SSP). The CoAl2O4NPs crystal size calculated on the W-H plots and the SSP method are in good agreement with the HRSEM Scherrer method.

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X-ray diffraction study of concentration depth profiles of binary alloy coatings during thermal diffusion: application to brass coating

Journal of Applied Crystallography ◽

10.1107/s0021889898009765 ◽

1999 ◽

Vol 32 (1) ◽

pp. 27-35 ◽

Cited By ~ 5

Author(s):

B. Bolle ◽

A. Tidu ◽

J. J. Heizmann

Keyword(s):

Thermal Diffusion ◽

Profile Analysis ◽

Nondestructive Method ◽

Line Profile Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Depth Profiles ◽

Diffraction Line Profile ◽

Concentration Depth Profile ◽

Concentration Depth Profiles

Using the Houska method based on X-ray diffraction-line profile analysis, new mathematical treatments are proposed to compute directly the concentration depth profile of thin films obtained by diffusion. As an example, concentration depth profiles of a brass layer have been studied during the thermal diffusion process. This nondestructive method is fast (a few minutes) and allows the sample to be used for complementary analysis if necessary.

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Estimation of Lattice Strain in Lanthanum Hexa Aluminate Nanoparticles Using X-Ray Peak Profile Analysis

Revue des composites et des matériaux avancés ◽

10.18280/rcma.310102 ◽

2021 ◽

Vol 31 (1) ◽

pp. 13-19

Author(s):

Naga Venkata Sai Ram Yellapragada ◽

Tara Sasanka Cherukuri ◽

Prabakaran Jayaraman ◽

Sameer Kumar Devarakonda

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Crystallite Size ◽

Profile Analysis ◽

Xrd Analysis ◽

Nano Particles ◽

X Ray ◽

Peak Broadening ◽

Average Grain Size ◽

Scanning Electron

This work confers to the preparation of Lanthanum Hexa Aluminate (LHA) nanoparticles by chemical precipitation and filtration technique followed by characterization studies conducted through X-ray peak profile analysis (XPPA) and Field Emission Scanning Electron Microscopy (FESEM) supported by Energy Dispersive Spectroscopy (EDS). From the X-ray diffraction (XRD) analysis, it has been observed that the prepared powder has hexagonal crystal structure. Further, Scherrer Method (S-M), modified Williamson–Hall (W-H), and Size–Strain Plot (SSP) methods have been implemented to all LHA reflection peaks for the comprehensive crystalline analysis. The influence of crystallite size, stress, strain, and energy density values on the peak broadening of LHA nanoparticles has been critically examined and discussed in the current work. In addition to regular mathematical models this paper also provides an insight into the calculation of Youngs modulus without tedious experimental procedure. The predicted crystallite size estimated from Scherrer’s formula, and W-H models are correlated to scanning electron microscopy results and observed that the average grain size of LHA nano particles estimated from SEM analysis, and models have less deviation in the present study.

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Characterizing dislocation loops in irradiated polycrystalline Zr alloys by X-ray line profile analysis of powder diffraction patterns with satellites

Journal of Applied Crystallography ◽

10.1107/s1600576721002673 ◽

2021 ◽

Vol 54 (3) ◽

Author(s):

Tamás Ungár ◽

Gábor Ribárik ◽

Matthew Topping ◽

Rebecca M. A. Jones ◽

Xiao Dan Xu ◽

...

Keyword(s):

Dislocation Density ◽

Powder Diffraction ◽

Profile Analysis ◽

Line Profile Analysis ◽

Dislocation Loops ◽

Total Dislocation Density ◽

Diffraction Patterns ◽

Induced Dislocation ◽

Zr Alloys

This work extends the convolutional multiple whole profile (CMWP) line profile analysis (LPA) procedure to determine the total dislocation density and character of irradiation-induced dislocation loops in commercial polycrystalline Zr specimens. Zr alloys are widely used in the nuclear industry as fuel cladding materials in which irradiation-induced point defects evolve into dislocation loops. LPA has long been established as a powerful tool to determine the density and nature of lattice defects in plastically deformed materials. The CMWP LPA procedure is based on the Krivoglaz–Wilkens theory in which the dislocation structure is characterized by the total dislocation density ρ and the dislocation arrangement parameter M. In commercial Zr alloys irradiation-induced dislocation loops broaden the peak profiles, mainly in the tail regions, and occasionally generate small satellites next to the Bragg peaks. In this work, two challenges in powder diffraction patterns of irradiated Zr alloys are solved: (i) determination of the M values from the long tail regions of peaks has been made unequivocal and (ii) satellites have been fitted separately, using physically well established principles, in order to exclude them from the dislocation determination process. Referring to the theory of heterogeneous dislocation distributions, determination of the total dislocation density from the main peaks free of satellites has been justified. The dislocation loop structure has been characterized by the total dislocation density of loops and the M parameter correlated to the dipole character of dislocation loops. The extended CMWP procedure is applied to determine the total dislocation density, the dipole character of dislocation loops, and the fractions of 〈a〉- and 〈c〉-type loops in proton- or neutron-irradiated polycrystalline Zr alloys used in the nuclear energy industry.

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Point Defect Absorption and Dislocation Loop Formation at Grain Boundaries in Hvem-Irradiated Zr and Its Alloys:1. Influence of Solute Addition

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010011862x ◽

1985 ◽

Vol 43 ◽

pp. 350-351

Author(s):

R.A. Herring ◽

M. Griffiths ◽

M.H Loretto ◽

R.E. Smallman

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Point Defect ◽

Reactor Core ◽

Solute Concentration ◽

Nuclear Industry ◽

Dislocation Loops ◽

Loop Formation ◽

Component Material ◽

Impurity Interaction

Because Zr is used in the nuclear industry to sheath fuel and as structural component material within the reactor core, it is important to understand Zr's point defect properties. In the present work point defect-impurity interaction has been assessed by measuring the influence of grain boundaries on the width of the zone denuded of dislocation loops in a series of irradiated Zr alloys. Electropolished Zr and its alloys have been irradiated using an AEI EM7 HVEM at 1 MeV, ∼675 K and ∼10-6 torr vacuum pressure. During some HVEM irradiations it has been seen that there is a difference in the loop nucleation and growth behaviour adjacent to the grain boundary as compared with the mid-grain region. The width of the region influenced by the presence of the grain boundary should be a function of the irradiation temperature, dose rate, solute concentration and crystallographic orientation.

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Highlights in the history of X-ray topography1

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1524/zkri.1995.210.6.394 ◽

1995 ◽

Vol 210 (6) ◽

Author(s):

A. R. Lang

Keyword(s):

Magnetic Domain ◽

Diffraction Theory ◽

Dislocation Loops ◽

X Ray Diffraction ◽

X Ray ◽

Domain Structures ◽

Structure Factors ◽

History Of ◽

Dislocation Sources ◽

Non Destructive

AbstractX-ray topography provides a non-destructive method of mapping point-by-point variations in orientation and reflecting power within crystals. The discovery, made by several workers independently, that in nearly perfect crystals it was possible to detect individual dislocations by X-ray diffraction contrast started an epoch of rapid exploitation of X-ray topography as a new, general method for assessing crystal perfection. Another discovery, that of X-ray Pendellösung, led to important theoretical developments in X-ray diffraction theory and to a new and precise method for measuring structure factors on an absolute scale. Other highlights picked out for mention are studies of Frank-Read dislocation sources, the discovery of long dislocation helices and lines of coaxial dislocation loops in aluminium, of internal magnetic domain structures in Fe-3 wt.% Si, and of stacking faults in silicon and natural diamonds.

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Microstructure of post-deformed ECAP-Ti investigated by Multiple X-Ray Line Profile Analysis

Zeitschrift für Kristallographie Supplements ◽

10.1524/zksu.2006.suppl_23.129 ◽

2006 ◽

Vol 2006 (suppl_23_2006) ◽

pp. 129-134 ◽

Cited By ~ 6

Author(s):

E. Schafler ◽

K. Nyilas ◽

S. Bernstorff ◽

L. Zeipper ◽

M. Zehetbauer ◽

...

Keyword(s):

Line Profile ◽

Profile Analysis ◽

Line Profile Analysis ◽

X Ray

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Multi-exposure X-ray image fusion quality evaluation based on CSF and gradient amplitude similarity

Journal of X-Ray Science and Technology ◽

10.3233/xst-210871 ◽

2021 ◽

pp. 1-13

Author(s):

Yanjie Qi ◽

Zehui Yang ◽

Lin Kang

Keyword(s):

Image Fusion ◽

Quality Evaluation ◽

Evaluation Method ◽

Dynamic Range ◽

Reference Image ◽

Subjective Perception ◽

Steel Component ◽

Imaging Device ◽

X Ray ◽

Gradient Amplitude

Due to the limitation of dynamic range of the imaging device, the fixed-voltage X-ray images often produce overexposed or underexposed regions. Some structure information of the composite steel component is lost. This problem can be solved by fusing the multi-exposure X-ray images taken by using different voltages in order to produce images with more detailed structures or information. Due to the lack of research on multi-exposure X-ray image fusion technology, there is no evaluation method specially for multi-exposure X-ray image fusion. For the multi-exposure X-ray fusion images obtained by different fusion algorithms may have problems such as the detail loss and structure disorder. To address these problems, this study proposes a new multi-exposure X-ray image fusion quality evaluation method based on contrast sensitivity function (CSF) and gradient amplitude similarity. First, with the idea of information fusion, multiple reference images are fused into a new reference image. Next, the gradient amplitude similarity between the new reference image and the test image is calculated. Then, the whole evaluation value can be obtained by weighting CSF. In the experiments of MEF Database, the SROCC of the proposed algorithm is about 0.8914, and the PLCC is about 0.9287, which shows that the proposed algorithm is more consistent with subjective perception in MEF Database. Thus, this study demonstrates a new objective evaluation method, which generates the results that are consistent with the subjective feelings of human eyes.

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