Inhomogeneous Distribution of Dislocation Density as Manifestation of Multiscale Structure in Tubes from Zr - Based Alloys

2003 ◽  
Vol 779 ◽  
Author(s):  
Yuriy Perlovich ◽  
Margarita Isaenkova
Keyword(s):  
Dislocation Density ◽  
Domain Size ◽  
Nuclear Industry ◽  
Ray Method ◽  
Coherent Domain Size ◽  
Texture Measurement ◽  
Burgers Vector ◽  
X Ray ◽  
Pole Figures ◽  
Coherent Domain

AbstractAn X-ray method was developed to determine the dislocation density in metal materials as a distribution depending on the orientation of Burgers vector. The method includes 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 the generalized pole figures. The method was used to determine the dislocation density in tubes of Zr-based alloys for nuclear industry. Obtained data show, that the dislocation density varies within very wide interval of several orders of magnitude depending on the grain orientation both in as-rolled and annealed tubes. Features of the dislocation distribution in tubes are closely related to their crystallographic texture.

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.

Distributions of Domain Size, Lattice Distortion and Dislocation Density in Tubes of Zr-Based Alloys Studied by a Method Combining X-Ray Line Profile Analysis with Texture Measurements

2004 ◽  
Vol 443-444 ◽  
pp. 255-258 ◽  
Author(s):  
Yuriy Perlovich ◽  
Margarita Isaenkova
Keyword(s):  
Dislocation Density ◽  
Lattice Distortion ◽  
Profile Analysis ◽  
Domain Size ◽  
Line Profile Analysis ◽  
Ray Method ◽  
Texture Measurement ◽  
X Ray ◽  
Pole Figures ◽  
Line Analysis

The distributions of substructure parameters for tubes of Zr-based alloys were constructed by use of the X-ray method of Generalized Pole Figures, combining X-ray line analysis and texture measurement. Obtained distributions cover α-Zr crystallites of all orientations and give the fullest description of substructure features of the studied tubes. The interconnection of different substructure parameters are analyzed.

Features of Texture and Structure Development in Zirconium under Equal Channel Angular Pressing

2006 ◽  
Vol 503-504 ◽  
pp. 859-864 ◽  
Author(s):  
Yuriy Perlovich ◽  
Margarita Isaenkova ◽  
Vladimir Fesenko ◽  
M. Grekhov ◽  
Seng Ho Yu ◽  
...  
Keyword(s):  
Deformation Mechanisms ◽  
Line Profiles ◽  
Structure Development ◽  
Formation Theory ◽  
Ray Method ◽  
Texture Measurement ◽  
X Ray ◽  
Angular Pressing ◽  
Structure Changes ◽  
Pole Figures

A detailed X-ray study of Zr rods, subjected to ECAP at 350oC by routes C and BC, was conducted by the new X-ray method of Generalized Pole Figures, combining texture measurement with registration of X-ray line profiles. The data analysis is based on conceptions of the texture formation theory, connecting features of grain reorientation with activated deformation mechanisms. A degree of reproduction of the same distinctive texture by successive ECAP passes with antecedent rotation of the rod reflects attendant structure changes in material.

scholarly journals Dislocation density and Burgers vector population in fiber-textured Ni thin films determined by high-resolution X-ray line profile analysis

2012 ◽  
Vol 45 (1) ◽  
pp. 61-70 ◽  
Author(s):  
Gábor Csiszár ◽  
Karen Pantleon ◽  
Hossein Alimadadi ◽  
Gábor Ribárik ◽  
Tamás Ungár
Keyword(s):  
Thin Films ◽  
High Resolution ◽  
Dislocation Density ◽  
Line Profile ◽  
Profile Analysis ◽  
Domain Size ◽  
Line Profile Analysis ◽  
Burgers Vector ◽  
X Ray ◽  
Vector Population

Nanocrystalline Ni thin films have been produced by direct current electrodeposition with different additives and current density in order to obtain 〈100〉, 〈111〉 and 〈211〉 major fiber textures. The dislocation density, the Burgers vector population and the coherently scattering domain size distribution are determined by high-resolution X-ray diffraction line profile analysis. The substructure parameters are correlated with the strength of the films by using the combined Taylor and Hall–Petch relations. The convolutional multiple whole profile method is used to obtain the substructure parameters in the different coexisting texture components. A strong variation of the dislocation density is observed as a function of the deposition conditions.

The Influence of Errors of X-Ray Texture Measurements on ODF Calculation with Central Normal Distribution Approximation

2005 ◽  
Vol 495-497 ◽  
pp. 273-276
Author(s):  
T.M. Ivanova ◽  
H.U. Lubman ◽  
T.I. Savyolova ◽  
Vladimir Serebryany
Keyword(s):  
Normal Distribution ◽  
Measurement Errors ◽  
Orientation Distribution ◽  
Pole Density ◽  
Hexagonal Symmetry ◽  
Ray Method ◽  
Texture Measurement ◽  
Crystal Direction ◽  
X Ray ◽  
Pole Figures

Experimental pole figures are measured by x-ray method for materials with hexagonal symmetry (Ti and Mg alloys). The Orientation Distribution Function is calculated by approximation method with central normal distribution. Texture inhomogeneities and effects of defocusing are the main sources of pole density errors. The measurement errors depend on crystal direction {hkl} and are different for maximum and minimum regions on pole figure. The influence of texture measurement errors on accuracy of the ODF calculation is investigated.

Combined texture and microstructure analysis of deformed crystals by high-energy X-ray diffraction

2018 ◽  
Vol 51 (3) ◽  
pp. 883-894 ◽  
Author(s):  
Hao Yuan ◽  
Zhe Chen ◽  
Thomas Buslaps ◽  
Veijo Honkimäki ◽  
András Borbély
Keyword(s):  
Profile Analysis ◽  
Domain Size ◽  
Lorentz Factor ◽  
High Energy ◽  
Microstructure Analysis ◽  
Line Profile Analysis ◽  
X Ray Diffraction ◽  
Coherent Domain Size ◽  
X Ray ◽  
Coherent Domain

It is shown that high-energy X-ray diffraction allows a fast and accurate texture and microstructure analysis of crystals, which can help to set up optimal industrial procedures for materials manufacturing. This paper presents the experimental and theoretical aspects of quantitative texture analysis using high-energy synchrotron beams. Intensity corrections are less important in this approach than in classical laboratory methods; however, the most important correction, related to the Lorentz factor, can introduce relative fraction changes of up to about 40% compared to the uncorrected case. The resolution of the orientation density function also influences the results. For example, the usual 5° resolution leads to relative deviations of up to 30% in the fraction of some components. The method allowed detection of small changes taking place during the recovery and continuous recrystallization of a cold-rolled Al–TiB2 nanocomposite. Texture information was combined with the results of line profile analysis, evidencing the evolution of the average dislocation density and coherent domain size of the selected grain families. It was found that recovery, as described in terms of dislocation annihilation and coherent domain coarsening, takes place at similar rates in all components.

New Principles of the Substructure Development in Metal Materials under Plastic Deformation, Revealed by Advanced X-Ray Methods

2004 ◽  
Vol 443-444 ◽  
pp. 259-262 ◽  
Author(s):  
Yuriy Perlovich ◽  
Margarita Isaenkova
Keyword(s):  
Wide Spectrum ◽  
Residual Deformation ◽  
Ray Method ◽  
Computer Data ◽  
Rolled Material ◽  
X Ray ◽  
Pole Figures ◽  
Metal Materials ◽  
First Time ◽  
Ray Methods

The substructure inhomogeneity of real textured metal materials was studied by use of the X-ray method of Generalized Pole Figures and the computer data treatment. Main regularities of substructure inhomogeneity were revealed for the first time. Substructure conditions of grains in rolled material form an extremely wide spectrum and vary by passing from texture maxima to texture minima, where residual deformation effects are most significant. The distribution of residual elastic microstrains in the orientational space of rolled material shows the distinct system.

scholarly journals Superconducting properties of very high quality NbN thin films grown by pulsed laser deposition

2019 ◽  
Vol 70 (7) ◽  
pp. 89-94
Author(s):  
Serhii Volkov ◽  
Maros Gregor ◽  
Tomas Roch ◽  
Leonid Satrapinskyy ◽  
Branislav Grančič ◽  
...  
Keyword(s):  
Thin Films ◽  
Transition Temperature ◽  
Superconducting Transition Temperature ◽  
Pulsed Laser ◽  
Domain Size ◽  
Superconducting Transition ◽  
Superconducting Properties ◽  
Si Substrate ◽  
Coherent Domain Size ◽  
Coherent Domain

Abstract In this work, we study the effect of the various substrates on the growth and superconducting properties of NbN thin films grown by using pulsed laser ablation in a N2 + 1%H2 atmosphere on MgO, Al2O3 and Si substrates. Structural and superconducting analyses of the films demonstrate that using MgO and Al2O3 substrates can significantly improve the film properties compared to Si substrate. The X-ray diffraction data indicate that MgO and Al2O3 substrates produce highly oriented superconducting NbN films with large coherent domain size in the out-of plane direction on the order of layer thickness and with a superconducting transition temperature of 13.1 K and 15.2 K, respectively. On the other hand, the NbN film grown on the Si substrate exhibits random polycrystalline orientation. Together with the smallest coherent domain size it leads to the lower critical temperature of 8.3 K. Finally, by using a passivation surface layer we are able to improve superconducting properties of NbN thin film and we observe superconducting transition temperature 16.6 K, the one of the highest value reported so far for 50 nm thick NbN film on sapphire.

Use of X-Ray Curved Sensitive Position Detector for Simultaneous Measurement of Several Pole Figures

1986 ◽  
Vol 30 ◽  
pp. 421-427
Author(s):  
J.J. Heizmann ◽  
C. Laruelle ◽  
A. Vadon
Keyword(s):  
Pole Figure ◽  
Simultaneous Measurement ◽  
Texture Measurement ◽  
X Ray ◽  
Pole Figures ◽  
Position Sensitive ◽  
Lattice Planes ◽  
The Moment ◽  
Time Required ◽  
The Cost

At the moment, the time required to obtain a pole figure is about three hours, and generally several pole figures are needed to make a texture analysis. Therefore the time and the cost of texture measurement are widely increased.Now, new position sensitive X-Ray detectors are appearing, which allow to record at one and the same time the whole 2Θ spectrum, i.e. the beams diffracted by several (hi k1l1) lattice planes. So with this kind of detector, it will be possible to get simultaneously several pole figures.

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