scholarly journals Determination of Local Strains in a Neighborhood of Cracks in a Welded Seam of Ni-Cr-Fe According to the Power Fourier Spectrum of Kikuchi Patterns

2018 ◽  
Vol 19 (4) ◽  
pp. 307-312 ◽  
Author(s):  
M.D. Borcha ◽  
M.S. Solodkyi ◽  
S.V. Balovsyak ◽  
I.M. Fodchuk ◽  
A.R. Kuzmin ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Gaussian Noise ◽  
Fourier Spectrum ◽  
Electron Backscatter Diffraction ◽  
Two Dimensional ◽  
Electron Backscatter ◽  
Diffraction Patterns ◽  
Welded Seam ◽  
Backscatter Diffraction

A discrete two-dimensional Fourier transform and the power Fourier spectrum are used for determination of average strains near cracks in a welded seam of Ni-Cr-Fe alloy. The alignment of Kikuchi images with the help of genetic algorithms and subtraction of white Gaussian noise made it possible to more fully take into account the influence of instrumental factors on the formation of electron backscatter diffraction patterns.

Investigation of Low Symmetry Crystals Using Elctron Backscatter Diffraction

1999 ◽  
Vol 5 (S2) ◽  
pp. 222-223
Author(s):  
D.J. Dingley
Keyword(s):  
Pattern Recognition ◽  
Electron Backscatter Diffraction ◽  
Zone Axis ◽  
Two Dimensional ◽  
Electron Backscatter ◽  
Automated Pattern Recognition ◽  
Diffraction Patterns ◽  
Pass Through ◽  
Backscatter Diffraction ◽  
Low Symmetry

Electron backscatter diffraction patterns obtained from low symmetry crystals can present difficulties for automated pattern recognition. For example, when only a single zone axis is observed in the diffraction pattern and the Kikuchi bands used for indexing all pass through the zone axis then only two-dimensional crystallographic information is obtained. This results in there being a 180 degree ambiguity in the measured orientation. Furthermore, it is often observed that in automated indexing of quartz, an additional ambiguity is introduced when the zone axis imaged is [0001]. In this case it is difficult to distinguish between the true orientation and it’s twin. This ambiguity is overcome only if Kikuchi bands from the upper Laue zones are used in the indexing. However, in automated indexing it is normal for the computer to select the strongest Kikuchi bands visible and these will not be those from the upper Laue zones when the [0001] zone axis is imaged. This and other pseudo symmetries have been observed and have been overcome by applying correction procedures during data collection and in post collection analysis.

scholarly journals Determination of Crystal Structure from Electron Backscatter Diffraction Patterns

2009 ◽  
Vol 15 (S2) ◽  
pp. 766-767 ◽  
Author(s):  
SI Wright ◽  
DJ Dingley ◽  
MM Nowell
Keyword(s):  
Crystal Structure ◽  
Electron Backscatter Diffraction ◽  
Electron Backscatter ◽  
Diffraction Patterns ◽  
Backscatter Diffraction

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

Electron backscatter diffraction determination of grain orientation and constituent phases

1999 ◽  
Vol 4 (2) ◽  
pp. 174-174
Author(s):  
Chen Xiaomei ◽  
Liu Jing ◽  
Wang Jianbo ◽  
Zhang Ruikang ◽  
Wang Dahai ◽  
...  
Keyword(s):  
Grain Orientation ◽  
Electron Backscatter Diffraction ◽  
Diffraction Determination ◽  
Electron Backscatter ◽  
Backscatter Diffraction

Application of Electron Backscatter Diffraction for Crystallographic Characterization of Tin Whiskers

2012 ◽  
Vol 18 (4) ◽  
pp. 876-884 ◽  
Author(s):  
Joseph R. Michael ◽  
Bonnie B. McKenzie ◽  
Donald F. Susan
Keyword(s):  
Electron Backscatter Diffraction ◽  
Growth Direction ◽  
Tin Whiskers ◽  
Physical Growth ◽  
Final Choice ◽  
Advantages And Disadvantages ◽  
Electron Backscatter ◽  
Backscatter Diffraction

AbstractUnderstanding the growth of whiskers or high aspect ratio features on substrates can be aided when the crystallography of the feature is known. This study has evaluated three methods that utilize electron backscatter diffraction (EBSD) for the determination of the crystallographic growth direction of an individual whisker. EBSD has traditionally been a technique applied to planar, polished samples, and thus the use of EBSD for out-of-surface features is somewhat more difficult and requires additional steps. One of the methods requires the whiskers to be removed from the substrate resulting in the loss of valuable physical growth relationships between the whisker and the substrate. The other two techniques do not suffer this disadvantage and provide the physical growth information as well as the crystallographic growth directions. The final choice of method depends on the information required. The accuracy and the advantages and disadvantages of each method are discussed.

scholarly journals Crystal orientation and detector distance effects on resolving pseudosymmetry by electron backscatter diffraction

2021 ◽  
Vol 54 (2) ◽  
pp. 513-522
Author(s):  
Edward L. Pang ◽  
Christopher A. Schuh
Keyword(s):  
Crystal Orientation ◽  
Electron Backscatter Diffraction ◽  
Detector Distance ◽  
Recent Emergence ◽  
Distance Effects ◽  
Electron Backscatter ◽  
Sample Position ◽  
Position And Orientation ◽  
Diffraction Patterns ◽  
Backscatter Diffraction

Accurately indexing pseudosymmetric materials has long proven challenging for electron backscatter diffraction. The recent emergence of intensity-based indexing approaches promises an enhanced ability to resolve pseudosymmetry compared with traditional Hough-based indexing approaches. However, little work has been done to understand the effects of sample position and orientation on the ability to resolve pseudosymmetry, especially for intensity-based indexing approaches. Thus, in this work the effects of crystal orientation and detector distance in a model tetragonal ZrO2 (c/a = 1.0185) material are quantitatively investigated. The orientations that are easiest and most difficult to correctly index are identified, the effect of detector distance on indexing confidence is characterized, and these trends are analyzed on the basis of the appearance of specific zone axes in the diffraction patterns. The findings also point to the clear benefit of shorter detector distances for resolving pseudosymmetry using intensity-based indexing approaches.

Error analysis of the crystal orientations and disorientations obtained by the classical electron backscatter diffraction technique

2015 ◽  
Vol 48 (3) ◽  
pp. 797-813 ◽  
Author(s):  
Farangis Ram ◽  
Stefan Zaefferer ◽  
Tom Jäpel ◽  
Dierk Raabe
Keyword(s):  
Electron Diffraction ◽  
Electron Backscatter Diffraction ◽  
Diffraction Theory ◽  
Classical Electron ◽  
Accuracy Measure ◽  
Electron Backscatter ◽  
Analytical Accuracy ◽  
Precision And Accuracy ◽  
Diffraction Patterns ◽  
Backscatter Diffraction

The fidelity – that is, the error, precision and accuracy – of the crystallographic orientations and disorientations obtained by the classical two-dimensional Hough-transform-based analysis of electron backscatter diffraction patterns (EBSPs) is studied. Using EBSPs simulated based on the dynamical electron diffraction theory, the fidelity analysis that has been previously performed using the patterns simulated based on the theory of kinematic electron diffraction is improved. Using the same patterns, the efficacy of a Fisher-distribution-based analytical accuracy measure for orientation and disorientation is verified.

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