Determination of the Sense of Burgers Vector by Plane-Wave X-ray Topography

1983 ◽  
Vol 22 (Part 2, No. 3) ◽  
pp. L151-L153
Author(s):  
Kohtaro Ishida ◽  
Yoshinori Kobayashi ◽  
Hiroyuki Katoh ◽  
Satio Takagi
Keyword(s):  
Plane Wave ◽  
Burgers Vector ◽  
X Ray

Distribution of Dislocation Density in Tubes from Zr-Based Alloys by X-Ray Data

2005 ◽  
Vol 105 ◽  
pp. 89-94 ◽  
Author(s):  
Margarita Isaenkova ◽  
Yuriy Perlovich
Keyword(s):  
Dislocation Density ◽  
Domain Size ◽  
Ray Method ◽  
Coherent Domain Size ◽  
Texture Measurement ◽  
Burgers Vector ◽  
X Ray ◽  
Pole Figures ◽  
Coherent Domain

As applied to tubes from Zr-based alloys, the X-ray method was developed to determine the dislocation density distribution in a-Zr depending on the orientation of Burgers vector. The method consists in registration of X-ray line profiles by each successive position of the sample in the course of diffractometric texture measurement using reflections of two orders, the following determination of coherent domain size and lattice distortion by means of the Warren-Averbach method for each orientation of reflecting planes, separate calculation of the density of c- and a-dislocations with all possible orientations of Burgers vector and presentation of results in generalized pole figures. Obtained data testify that the dislocation density varies within very wide intervals of several orders of magnitude depending on the grain orientation both in as-rolled and annealed tubes. Features of the constructed dislocation distributions are closely related to the crystallographic texture of studied tubes.

Determination of Burgers Vector of Screw Dislocations in 6H-SiC Single Crystals by Synchrotron White Beam X-Ray Topography

1996 ◽  
Vol 437 ◽  
Author(s):  
W. Si ◽  
M. Dudley ◽  
C. Carter ◽  
R. Glass ◽  
V. Tsvetkov
Keyword(s):  
Single Crystals ◽  
Dislocation Core ◽  
Line Defect ◽  
Screw Dislocations ◽  
Burgers Vector ◽  
X Ray ◽  
White Beam ◽  
Lattice Planes ◽  
Vector Magnitude

AbstractIndividual screw dislocations along the [0001] axis in 6H-SiC single crystals have been characterized by means of Synchrotron White Beam X-ray Topography (SWBXT). The magnitude of the Burgers vector was determined from: (1) the diameter of circular diffraction-contrast images of dislocations in back-reflection topographs, (2) the width of bi-modal images associated with screw dislocations in transmission topographs, (3) the magnitude of the tilt of the lattice planes on both sides of dislocation core in projection topographs, and (4) also the magnitude of the tilt of the lattice planes in section topographs. All of the four methods showed reasonable consistency. The sense of the Burgers vector can also be deduced from the abovementioned tilt of the lattice planes. Results revealed that in 6H-SiC a variety of screw dislocations can be found with Burgers vector magnitude ranging from 1c to 7c (c is the lattice constant along [0001] axis). This work demonstrates that SWBXT can be used as a quantitative technique for detailed analyses of line defect configurations.

scholarly journals Direct determination of Burgers vector sense and magnitude of elementary dislocations by synchrotron white x-ray topography

2008 ◽  
Vol 103 (1) ◽  
pp. 013510 ◽  
Author(s):  
Daisuke Nakamura ◽  
Satoshi Yamaguchi ◽  
Yoshiharu Hirose ◽  
Toshihiko Tani ◽  
Kazumasa Takatori ◽  
...  
Keyword(s):  
Direct Determination ◽  
Burgers Vector ◽  
X Ray ◽  
Vector Sense

Lateral resolution of the electron microbeam analysis

1978 ◽  
Vol 36 (1) ◽  
pp. 542-543
Author(s):  
H.J. Dudek
Keyword(s):  
Quantitative Analysis ◽  
Depth Resolution ◽  
Lateral Resolution ◽  
Cylindrical Particle ◽  
Correction Procedure ◽  
X Ray ◽  
Element Concentrations ◽  
Microbeam Analysis ◽  
The Matrix

The chemical inhomogenities in modern materials such as fibers, phases and inclusions, often have diameters in the region of one micrometer. Using electron microbeam analysis for the determination of the element concentrations one has to know the smallest possible diameter of such regions for a given accuracy of the quantitative analysis.In th is paper the correction procedure for the quantitative electron microbeam analysis is extended to a spacial problem to determine the smallest possible measurements of a cylindrical particle P of high D (depth resolution) and diameter L (lateral resolution) embeded in a matrix M and which has to be analysed quantitative with the accuracy q. The mathematical accounts lead to the following form of the characteristic x-ray intens ity of the element i of a particle P embeded in the matrix M in relation to the intensity of a standard S

Sem and X-Ray Analysis of Renal and Biliary Calculi

1976 ◽  
Vol 34 ◽  
pp. 306-307
Author(s):  
R. J. Narconis ◽  
G. L. Johnson
Keyword(s):  
Chemical Constituents ◽  
Natural State ◽  
X Ray Diffraction ◽  
Chemical Methods ◽  
X Ray ◽  
Additional Dimension ◽  
Biliary Calculi ◽  
Calculus Formation ◽  
Scanning Electron

Analysis of the constituents of renal and biliary calculi may be of help in the management of patients with calculous disease. Several methods of analysis are available for identifying these constituents. Most common are chemical methods, optical crystallography, x-ray diffraction, and infrared spectroscopy. The application of a SEM with x-ray analysis capabilities should be considered as an additional alternative.A scanning electron microscope equipped with an x-ray “mapping” attachment offers an additional dimension in its ability to locate elemental constituents geographically, and thus, provide a clue in determination of possible metabolic etiology in calculus formation. The ability of this method to give an undisturbed view of adjacent layers of elements in their natural state is of advantage in determining the sequence of formation of subsequent layers of chemical constituents.

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