scholarly journals Neutron Texture Analysis of Melt-Textured YBCO Bulk Samples

1999 ◽  
Vol 33 (1-4) ◽  
pp. 75-92
Author(s):  
Lothar Schmidt ◽  
Martin Ullrich ◽  
Werner F. Kuhs
Keyword(s):  
Quantitative Analysis ◽  
Texture Analysis ◽  
Pole Figure ◽  
Error Estimation ◽  
Superconducting Phase ◽  
Ybco Bulk ◽  
Pole Figures ◽  
Counting Statistics

Neutron texture measurements on YBCO bulk samples show a very sharp texture of the superconducting phase YBa2Cu3O7-x with half-widths of less than 5°. Even with a rather coarse measurement grid of only 722 points per complete pole figure, satisfactory results for the recalculated (002) pole figures could be obtained. However, for a reliable calculation of a complete ODF, finer grids will have to be used. Due to the importance of a good alignment of the c-axes in the material, a quantitative analysis of the (002) pole figures, including an error estimation due to measurement grid and counting statistics, was made. An outline for the determination of a reliable background estimate is given.

scholarly journals Minimal Pole Figure Ranges for Quantitative Texture Analysis

1992 ◽  
Vol 19 (1-2) ◽  
pp. 45-54 ◽  
Author(s):  
K. Helming
Keyword(s):  
Texture Analysis ◽  
Pole Figure ◽  
Practical Interest ◽  
Texture Measurement ◽  
Pole Figures

The use of only a small number of incomplete pole figures for texture determinations is of practical interest for reducing the effort of texture measurement. The determination of minimal pole figure ranges (MPR) is explained and the use of MPR is demonstrated on an example.

scholarly journals Volume Texture of a Deformed Quartzite Observed With U-Stage Microscopy and Neutron Diffractometry

1999 ◽  
Vol 31 (4) ◽  
pp. 239-248 ◽  
Author(s):  
H. Ghildiyal ◽  
E. Jansen ◽  
A. Kirfel
Keyword(s):  
Neutron Diffraction ◽  
Pole Figure ◽  
North West ◽  
Pole Figures ◽  
Slip Planes ◽  
Subsequent Calculation ◽  
Kaoko Belt ◽  
Universal Stage ◽  
Active Slip

The volume texture of a naturally deformed quartzite from the Kaoko belt, North-West Namibia, has been analysed by both universal stage microscopy and neutron diffraction. Universal stage microscopy is restricted to the determination of the base pinacoid preferred orientation in quartzite. For a more complete description of the texture, the orientations of additional crystal planes, such as first and second order prisms as well as positive and negative rhombs, must be known. Neutron methods allow the evaluation of pole figures of all Bragg reflecting planes, of which those of the first order prisms being considered to be the most active slip planes, are of particular interest. Drawbacks of neutron diffraction, i.e. the faking of an eventually absent inversion centre and lack of resolution, can be overcome by pole figure inversion and subsequent calculation of desired pole figures. Both, universal stage microscopy and neutron diffraction yield well comparable results, of course only with respect to the pole figure of the c-axis.

scholarly journals An Analytical Method for the Quantitative Determination of the Volume Fractions in Fiber Textures

1979 ◽  
Vol 3 (2) ◽  
pp. 73-83 ◽  
Author(s):  
Ivan Tomov ◽  
H. J. Bunge
Keyword(s):  
Quantitative Determination ◽  
Pole Figure ◽  
Angular Range ◽  
Asymmetric Unit ◽  
Normalization Factor ◽  
Measured Intensity ◽  
Volume Fractions ◽  
Pole Figures ◽  
Axis Of Symmetry

In order to evaluate pole-figure measurements quantitatively, one needs the normalization factor which reduces measured intensity values to multiples of the random density. This factor may be determined experimentally by measuring the intensities of a random sample or it may be calculated by integrating over the whole pole-figure or its asymmetric unit. If pole-figure values are not available in the whole angular range 0≤φ≤90° (incomplete pole-figures), then the calculation is in general much more difficult and it usually presumes the knowledge of several pole-figures.In the case of fiber textures (axial symmetry), consisting of only a few strongly preferred orientations with the crystal directions 〈uvw〉i parallel to the axis of symmetry, the normalization factor and hence the volume fractions of the components i may be calculated in a rather simple way requiring only one, possibly incomplete, pole figure.

Texture Analysis with Area Detectors

2005 ◽  
Vol 105 ◽  
pp. 71-76 ◽  
Author(s):  
Kurt Helming ◽  
Uwe Preckwinkel
Keyword(s):  
Texture Analysis ◽  
Pole Figure ◽  
Data Sets ◽  
Angle Of Incidence ◽  
Surface Layers ◽  
Area Detector ◽  
Texture Information ◽  
Pole Figures ◽  
Information Depth

Starting from simple geometric considerations concerning directions and orientations, intelligent strategies for pole figure measurements were developed for the area detector. The amount and quality of texture information contained in measured or available data sets can be directly controlled. The texture approximation is done by the component method. The method does not have any restrictions concerning the grids of sample directions in the pole figures. An almost constant information depth can be obtained at a low angle of incidence of the primary beam for the study of thin surface layers.

A Method for Obtaining a Quantitative Pole Figure of Stretched Rubber

1957 ◽  
Vol 1 ◽  
pp. 131-142
Author(s):  
Otto Renius
Keyword(s):  
Pole Figure ◽  
Alpha Angle ◽  
Geiger Counter ◽  
Rubber Latex ◽  
X Ray ◽  
Outer Portion ◽  
Transmission Technique ◽  
Pole Figures ◽  
Orientation Pattern

AbstractWork at the Detroit Arsenal has shown that techniques similar to those employed for the determination of pole figures of metals can be utilized for studying organic materials such a a stretched rubber latex. The rubber, when stretched, forms a preferred orientation pattern which is proportional in intensity to the degree of elongation, and which can be used to plot a pole figure.A Geiger-counter spectrometer was used to study samples of rubber stretched 600 to 1000 per cent. Using a transmission technique, the specimens were tilted to the impinging X-ray beam in five degree increments while rotating through 360 degrees to allow the measurement of the diffracted beam from the selected atomic planes at various angles within the specimen. The intensities of the diffracted beam at these angles were plotted on a stereographic net to form the pole figures of the (002) and (012) planes of the stretched rubber. The geometry of the sample arrangements permitted the outer portion of the pole figure to be plotted from alpha angle 0 degrees to alpha angle 45 degrees.

scholarly journals Normalizing Incomplete Experimental Pole Figures by Means of the Vector Method

1984 ◽  
Vol 6 (2) ◽  
pp. 97-103 ◽  
Author(s):  
H. Schaeben ◽  
A. Vadon
Keyword(s):  
Texture Analysis ◽  
Pole Figure ◽  
Axial Symmetry ◽  
Full Range ◽  
Inverse Pole Figure ◽  
Vector Method ◽  
Pole Figures ◽  
The Matrix

The vector method of quantitative texture analysis provides a new solution of the problem of normalizing incomplete experimental pole figures. It basically makes use of the fact that the matrix σ*(hkl) to which the corresponding matrix σ(hkl) reduces in case of: (1) axial symmetry in terms of pole figures; or (2) fiber textures in terms of orientations, is full range. In this case σ*(hkl) actually establishes the correspondence between the axial symmetrical direct pole figure and the corresponding inverse pole figure with respect to the normal ON of the sample.

Improvements in the Quantitative Evaluation of Three-Dimensional Texture. II. The Pole-Figure-Multiplying Method

1995 ◽  
Vol 28 (5) ◽  
pp. 532-533 ◽  
Author(s):  
L.-G. Yu ◽  
H. Guo ◽  
B. C. Hendrix ◽  
K.-W. Xu ◽  
J.-W. He
Keyword(s):  
Distribution Function ◽  
Texture Analysis ◽  
Pole Figure ◽  
Quantitative Evaluation ◽  
Orientation Distribution Function ◽  
Three Dimensional ◽  
Orientation Distribution ◽  
Simple Method ◽  
Pole Figures

A new simple method is proposed for determining the orientation distribution function (ODF) for three-dimensional texture analysis in a polycrystal based on the reality that the accuracy of an ODF is dependent on both the accuracy of each measured pole figure and the number of pole figures.

scholarly journals Comments to a Publication of T.I. Savyolova Concerning Domains of Dependence in Pole Figures

1998 ◽  
Vol 30 (3-4) ◽  
pp. 207-227 ◽  
Author(s):  
S. Matthies ◽  
C. Esling
Keyword(s):  
Texture Analysis ◽  
Pole Figure ◽  
Common Knowledge ◽  
Practical Importance ◽  
Three Dimensional ◽  
Data Sets ◽  
Starting Solution ◽  
Pole Figures ◽  
General Difference ◽  
Dimensional Object

A questionable publication of T.I. Savyolova is analysed. The paper claims, that it is possible to determine Ph(y) pole figure values for y∈Y(h;h0,Y0) using only data from y∈Y0 of a single pole figure Ph0(y). The contradiction to the common knowledge can be resolved well understanding that there is a general difference between the term solutions (or continuation of solutions) of an ultrahyperbolic equation (satisfied by the axis distribution function A(h, y)) and the term pole figure. Pole figures considered in texture analysis are two-dimensional projections of a three-dimensional object (the ODF f(g)). For limited data sets the equation ΔhA(h,y)=ΔyA(h,y) bears only a necessary, but not sufficient character in order to get solutions of interest, i.e. it cannot be guaranteed that a h-specific continuation of a starting solution Ph0(y) will be a “h-projection” of the same ODF, which belongs to a concrete sample and possesses the “h0-projection” Ph0(y).Consequently, to name such a h-specific continuation “pole figure” is incorrect. The consideration of formal (unambiguous only by artificial conditions) continuations of solutions may be mathematically interesting, but is of no practical importance for texture analysis. Examples (already considered by the authors about twenty years ago) are given, how to construct in a much more simple way continuations of solutions of the same useless type like in the paper under discussion.

scholarly journals The Determination of Crystallographic Textures From Selected Areas of a Specimen by Electron Diffraction

1983 ◽  
Vol 6 (1) ◽  
pp. 45-61 ◽  
Author(s):  
F. J. Humphreys
Keyword(s):  
Electron Microscope ◽  
Electron Diffraction ◽  
Diffraction Pattern ◽  
Pole Figure ◽  
Single Phase ◽  
Angular Resolution ◽  
Thin Foil ◽  
Two Phase ◽  
Pole Figures

A technique for the determination of partial pole figures with an angular resolution of <3°, from selected areas of a thin foil, is described. A microcomputer, interfaced to an unmodified JEOL 100 CX TEMSCAN electron microscope is used to scan a diffraction pattern over a detector, tilt the specimen in steps of 1.5° over a range of ±50°, and plot the resulting data as a semiquantitative pole figure. The application of the technique to the study of materials which deform inhomogeneously is discussed, and examples are given of pole figures obtained from deformed single phase and two phase aluminium specimens.

Study of the texture of polycrystalline FCC materials using one incomplete direct pole figure

2020 ◽  
Vol 86 (12) ◽  
pp. 32-39
Author(s):  
S. M. Mokrova ◽  
V. N. Milich
Keyword(s):  
Texture Analysis ◽  
Pole Figure ◽  
Texture Component ◽  
Optimal Number ◽  
Polycrystalline Materials ◽  
Reliability Parameters ◽  
Pole Figures ◽  
Polar Figure ◽  
Material Texture ◽  
Fcc Materials

The article deals with the algorithm for texture analysis of polycrystalline materials using one direct pole figure (DPF). It is shown that the incomplete direct polar figure {111} for fcc materials contains the necessary information about the material texture. The algorithm provides identification of the preferred texture components in a multicomponent texture material and determination of their properties. The proposed algorithm is as follows. The upper hemisphere of the digital representation of the DPF is scanned by a polar complex of vectors that are normal to the reflection planes. Then the reliability parameters for each orientation are calculated and a set of the most reliable orientations is formed. The chosen orientations are recalculated to the Rodrigues space wherein the preferred texture components are formed by clustering. At the same time, an iterative algorithm with symmetry operators is used to avoid the umklapp effect. Each texture component is represented by the following parameters: Rodrigues mean vector, Miller indices, and Euler angles. The share and scattering of the texture component are also calculated. A method for selecting the optimal number of clusters providing presentation of the texture with the desired degree of detail is proposed. This is achieved by comparing two incomplete direct pole figures taken for {111} and {200} to select the maximum cluster scattering value on which the number of formed predominant texture components depend. The developed algorithm seems promising for rapid texture analysis, in analysis of sharp and weak textures and when there are less than three DPFs.

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