scholarly journals Element-resolved Kikuchi pattern measurements of non-centrosymmetric materials

2017 ◽  
Vol 123 ◽  
pp. 328-338 ◽  
Author(s):  
Maarten Vos ◽  
Aimo Winkelmann
Keyword(s):  
Kikuchi Pattern

A very rapid in situ Kikuchi technique to determine relative crystal misorientation

1988 ◽  
Vol 46 ◽  
pp. 830-831
Author(s):  
J. I. Bennetch
Keyword(s):  
Electron Beam ◽  
Analytical Techniques ◽  
Superplastic Forming ◽  
The Other ◽  
Kikuchi Pattern ◽  
Kikuchi Line ◽  
Line Analysis

In a recent study of the superplastic forming (SPF) behavior of certain Al-Li-X alloys, the relative misorientation between adjacent (sub)grains proved to be an important parameter. It is well established that the most accurate way to determine misorientation across boundaries is by Kikuchi line analysis. However, the SPF study required the characterization of a large number of (sub)grains in each sample to be statistically meaningful, a very time-consuming task even for comparatively rapid Kikuchi analytical techniques.In order to circumvent this problem, an alternate, even more rapid in-situ Kikuchi technique was devised, eliminating the need for the developing of negatives and any subsequent measurements on photographic plates. All that is required is a double tilt low backlash goniometer capable of tilting ± 45° in one axis and ± 30° in the other axis. The procedure is as follows. While viewing the microscope screen, one merely tilts the specimen until a standard recognizable reference Kikuchi pattern is centered, making sure, at the same time, that the focused electron beam remains on the (sub)grain in question.

Dissociated Σ=27 boundaries in silicon

1988 ◽  
Vol 46 ◽  
pp. 624-625
Author(s):  
A. Garg ◽  
W.A.T. Clark ◽  
J.P. Hirth
Keyword(s):  
Electron Diffraction ◽  
Local Minimum ◽  
Boundary Energy ◽  
Coincidence Site Lattice ◽  
Boundary Plane ◽  
Low Energy ◽  
Theoretical Understanding ◽  
Site Lattice ◽  
Kikuchi Pattern ◽  
Analysis Techniques

In the last twenty years, a significant amount of work has been done in the theoretical understanding of grain boundaries. The various proposed grain boundary models suggest the existence of coincidence site lattice (CSL) boundaries at specific misorientations where a periodic structure representing a local minimum of energy exists between the two crystals. In general, the boundary energy depends not only upon the density of CSL sites but also upon the boundary plane, so that different facets of the same boundary have different energy. Here we describe TEM observations of the dissociation of a Σ=27 boundary in silicon in order to reduce its surface energy and attain a low energy configuration.The boundary was identified as near CSL Σ=27 {255} having a misorientation of (38.7±0.2)°/[011] by standard Kikuchi pattern, electron diffraction and trace analysis techniques. Although the boundary appeared planar, in the TEM it was found to be dissociated in some regions into a Σ=3 {111} and a Σ=9 {122} boundary, as shown in Fig. 1.

scholarly journals On the Use of EBSD and Microhardness to Study the Microstructure Properties of Tungsten Samples Prepared by Selective Laser Melting

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1215
Author(s):  
Mirza Atif Abbas ◽  
Yan Anru ◽  
Zhi Yong Wang
Keyword(s):  
Selective Laser Melting ◽  
Electron Backscatter Diffraction ◽  
Fusion Reactors ◽  
Laser Melting ◽  
Kikuchi Pattern ◽  
Plasma Facing Components ◽  
Electron Backscatter ◽  
Ebsd Technique ◽  
Temperature Exposure ◽  
Backscatter Diffraction

Additively manufactured tungsten and its alloys have been widely used for plasma facing components (PFCs) in future nuclear fusion reactors. Under the fusion process, PFCs experience a high-temperature exposure, which will ultimately affect the microstructural features, keeping in mind the importance of microstructures. In this study, microhardness and electron backscatter diffraction (EBSD) techniques were used to study the specimens. Vickers hardness method was used to study tungsten under different parameters. EBSD technique was used to study the microstructure and Kikuchi pattern of samples under different orientations. We mainly focused on selective laser melting (SLM) parameters and the effects of these parameters on the results of different techniques used to study the behavior of samples.

An observation of a kikuchi pattern during sputtering

1973 ◽  
Vol 27 (4) ◽  
pp. 999-1000 ◽  
Author(s):  
R. Browning ◽  
P. D. Townsend
Keyword(s):  
Kikuchi Pattern

LEED Kikuchi pattern: Phonon and plasmon contributions

1976 ◽  
Vol 54 (3) ◽  
pp. 580-592 ◽  
Author(s):  
A Mosser ◽  
Ch Burggraf ◽  
S Goldsztaub ◽  
Y.H Ohtsuki
Keyword(s):  
Kikuchi Pattern

ALCHEMI as holography

2001 ◽  
Vol 7 (S2) ◽  
pp. 350-351
Author(s):  
J.C.H. Spence ◽  
C. Koch
Keyword(s):  
Electron Beam ◽  
Spherical Wave ◽  
Point Sources ◽  
Two Dimensional ◽  
Small Thickness ◽  
Kikuchi Pattern ◽  
Diffraction Patterns

Two-dimensional Atom Location by Chanelling Enhanced Microanalysis ( Alchemi ) maps of characteristic Xray emission as function of the diffraction conditions of a 200kV electron beam hav been obtained from thin crystals by several workers . Reciprocity shows that these are equivalent to the diffraction patterns produced at infinity by 200kV point sources of electrons on atom sites, sue! as D in figure 1, for CsCl. Here ray SCD at left has been time-reversed at right. Using multislici superlattice simulations which launch a spherical wave from an atom site, we find that the resultinj Kikuchi pattern breaks up into separated blobs along the K-lines at small thickness, with one blol generated at infinity along each atomic string direction . Each blob (e.g. ID) is a Gabor in-lim hologram (e.g of atom C, formed by source S at right). Each source atom on equivalent sites (E, D produces identical holograms, whose intensities add.

Transmission Electron Microscopy studies of the structure of martensitic interfaces in Cu-Zn: Diffraction contrast

1990 ◽  
Vol 48 (4) ◽  
pp. 366-367
Author(s):  
F.-R. Chen ◽  
G. B. Olson
Keyword(s):  
Orientation Relationship ◽  
Parent Phase ◽  
Martensite Phase ◽  
Lattice Deformation ◽  
Kikuchi Pattern ◽  
Transmission Electron ◽  
Close Packed Structure ◽  
Bcc Structure ◽  
Image Position ◽  
Relationship Of

A Cu-38.6%Zn alloy was treated at 870°C and quenched in ice brine(10% NaOH) to produce martensitic transformation. The parent phase is bcc structure and the martensite phase is 9R close-packed structure. The orientation relationship of the parent phase and martensite was determined by the Kikuchi pattern and diffraction pattern. The experimental lattice deformation matrix can then be deduced from the orientation relationship and assumed correspondence. The lattice deformation matrices determined from experiment and calculated from CRAB martensite crystallography theory are as follows:As shown in Figure 1, a set of dislocations is observed in the martensitic interface whose Burgers vector is determined to be l/3[101]b by the two beam technique. The direction and the average spacing of these dislocations determined from experiment are [.49 . .47]b and 5±1nm respectively. This set of dislocations is consistent with the lattice invariant shear l/3[101]b on the ( 01)b plane with the magnitude 0.022 used in the CRAB martensite crystallography which corresponds to an anticoherency dislocation array with the spacing of 7.75nm and in the direction [.514,. ,.514]b. The habit plane determined from experiment is (.13,.65,.75 )b and close to (.13,.68,.72)b from the prediction of CRAB martensite crystallography.

Surface Rumpling of MgO(001) Deduced from Changes in RHEED Kikuchi Pattern. I. Experimental

1981 ◽  
Vol 50 (6) ◽  
pp. 2063-2068 ◽  
Author(s):  
Tetsuji Gotoh ◽  
Shunichi Murakami ◽  
Koreo Kinosita ◽  
Yoshitada Murata
Keyword(s):  
Kikuchi Pattern

Kikuchi bandlet method for the accurate deconvolution and localization of Kikuchi bands in Kikuchi diffraction patterns

2014 ◽  
Vol 47 (1) ◽  
pp. 264-275 ◽  
Author(s):  
Farangis Ram ◽  
Stefan Zaefferer ◽  
Dierk Raabe
Keyword(s):  
Diffraction Pattern ◽  
Shape Analysis ◽  
Fourier Space ◽  
Localization Accuracy ◽  
Kikuchi Pattern ◽  
Reflection Angle ◽  
Electron Backscatter ◽  
Diffraction Patterns ◽  
Limited Precision ◽  
Better Than

In order to retrieve crystallographic information from an electron backscatter Kikuchi diffraction pattern, its Kikuchi bands have to be localized. One of the main reasons for the limited precision of the present Kikuchi band localization methods is that the diffuse edges of a Kikuchi band are convoluted by many other Kikuchi bands that intersect them. To improve the localization accuracy, Kikuchi bands have to be deconvoluted. In this article, a new method for the deconvolution and localization of Kikuchi bands is presented. The deconvolution is based on the fact that, in a Kikuchi pattern, there are a number of Kikuchi bands that are not parallel to the bands that intersect them. It is performed in Fourier space. After deconvolution, localization is carried out by a quantitative shape analysis of the intensity profiles of the deconvoluted Kikuchi bands. Using the introduced method, for a real electron backscatter Kikuchi diffraction pattern with 45° half capture angle and 0.12° per pixel maximum scale factor, the characteristic hyperbolic features of the Kikuchi bands can be localized with a precision of better than 0.1° in reflection angle.

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