Energy-tunable x-ray diffraction: A tool for depth profiling in polycrystalline materials

2002 ◽  
Vol 73 (3) ◽  
pp. 1663-1667 ◽  
Author(s):  
E. Zolotoyabko ◽  
J. P. Quintana
Keyword(s):  
Depth Profiling ◽  
Polycrystalline Materials ◽  
X Ray Diffraction ◽  
X Ray

Micro Diffraction Imaging of Bulk Polycrystalline Materials

2006 ◽  
Vol 524-525 ◽  
pp. 273-278
Author(s):  
Thomas Wroblewski ◽  
A. Bjeoumikhov ◽  
Bernd Hasse
Keyword(s):  
High Spatial Resolution ◽  
Polycrystalline Materials ◽  
X Rays ◽  
X Ray Diffraction ◽  
Short Sample ◽  
X Ray ◽  
Detector Distance ◽  
Transmission Geometry ◽  
Diffraction Imaging ◽  
Position Sensitive

X-ray diffraction imaging applies an array of parallel capillaries in front of a position sensitive detector. Conventional micro channel plates of a few millimetre thickness have successfully been used as collimator arrays but require short sample to detector distances to achieve high spatial resolution. Furthermore, their limited absorption restricts their applications to low energy X-rays of around 10 keV. Progress in the fabrication of long polycapillaries allows an increase in the sample to detector distance without decreasing resolution and the use of high X-ray energies enables bulk investigations in transmission geometry.

2D real space visualization of d values in polycrystalline bulk materials of different hardness

2021 ◽  
Vol 54 (2) ◽  
pp. 597-603
Author(s):  
Mari Mizusawa ◽  
Kenji Sakurai
Keyword(s):  
Lattice Distortion ◽  
Structural Information ◽  
Hardness Test ◽  
Real Space ◽  
Polycrystalline Materials ◽  
X Rays ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Imaging ◽  
D Values

Conventional X-ray diffraction measurements provide some average structural information, mainly on the crystal structure of the whole area of the given specimen, which might not be very uniform and may include different crystal structures, such as co-existing crystal phases and/or lattice distortion. The way in which the lattice plane changes due to strain also might depend on the position in the sample, and the average information might have some limits. Therefore, it is important to analyse the sample with good lateral spatial resolution in real space. Although various techniques for diffraction topography have been developed for single crystals, it has not always been easy to image polycrystalline materials. Since the late 1990s, imaging technology for fluorescent X-rays and X-ray absorption fine structure has been developed via a method that does not scan either a sample or an X-ray beam. X-ray diffraction imaging can be performed when this technique is applied to a synchrotron radiation beamline with a variable wavelength. The present paper reports the application of X-ray diffraction imaging to bulk steel materials with varying hardness. In this study, the distribution of lattice distortion of hardness test blocks with different hardness was examined. Via this 2D visualization method, the grains of the crystals with low hardness are large enough to be observed by X-ray diffraction contrast in real space. The change of the d value in the vicinity of the Vickers mark has also been quantitatively evaluated.

X-Ray Diffraction

2021 ◽  
pp. 408-480
Author(s):  
Kannan M. Krishnan
Keyword(s):  
Point Group ◽  
Polycrystalline Materials ◽  
X Rays ◽  
X Ray Diffraction ◽  
Symmetry Point Group ◽  
X Ray ◽  
Atomic Scattering ◽  
Scattering Factor ◽  
Diffraction Patterns ◽  
Lattice Planes

X-rays diffraction is fundamental to understanding the structure and crystallography of biological, geological, or technological materials. X-rays scatter predominantly by the electrons in solids, and have an elastic (coherent, Thompson) and an inelastic (incoherent, Compton) component. The atomic scattering factor is largest (= Z) for forward scattering, and decreases with increasing scattering angle and decreasing wavelength. The amplitude of the diffracted wave is the structure factor, F hkl, and its square gives the intensity. In practice, intensities are modified by temperature (Debye-Waller), absorption, Lorentz-polarization, and the multiplicity of the lattice planes involved in diffraction. Diffraction patterns reflect the symmetry (point group) of the crystal; however, they are centrosymmetric (Friedel law) even if the crystal is not. Systematic absences of reflections in diffraction result from glide planes and screw axes. In polycrystalline materials, the diffracted beam is affected by the lattice strain or grain size (Scherrer equation). Diffraction conditions (Bragg Law) for a given lattice spacing can be satisfied by varying θ or λ — for study of single crystals θ is fixed and λ is varied (Laue), or λ is fixed and θ varied to study powders (Debye-Scherrer), polycrystalline materials (diffractometry), and thin films (reflectivity). X-ray diffraction is widely applied.

Residual Stress Depth-Profiling in Shot-Peened Al Alloy Components Subjected to Fatigue Testing

2010 ◽  
Vol 638-642 ◽  
pp. 2464-2469 ◽  
Author(s):  
Cristy Leonor Azanza Ricardo ◽  
G. Degan ◽  
M. Bandini ◽  
Paolo Scardi
Keyword(s):  
Residual Stress ◽  
Fatigue Testing ◽  
Depth Profiling ◽  
Cyclic Stress ◽  
Al Alloy ◽  
Stress Profile ◽  
X Ray Diffraction ◽  
X Ray ◽  
Residual Stress Profile ◽  
Number Of Cycles

The residual stress profile in a shot-peened Al alloy component was studied by a recently proposed method based on the known procedure of progressive thinning and X-ray Diffraction measurements. The effect the cyclic stress on the fatigue life was studied in detail, showing the correlation between nominal load and residual stress relaxation. Besides showing the expected decrease of compressive stress with the load and number of cycles, the present work highlights the importance of changes in the through-the-thickness residual stress distribution.

Ion Irradiation Effects in Solid Oxide Fuel Cell Electrolytes

2003 ◽  
Vol 801 ◽  
Author(s):  
Jeremy Cheng ◽  
Rojana Pornprasertsuk ◽  
Yuji Saito ◽  
Fritz B. Prinz
Keyword(s):  
Ion Irradiation ◽  
Depth Profiling ◽  
Surface Conductance ◽  
Dislocation Network ◽  
Ion Diffusion ◽  
X Ray Diffraction ◽  
Saturation Point ◽  
X Ray ◽  
Cell Electrolytes ◽  
Fuel Cell Electrolytes

ABSTRACTSingle crystal Ytrria-stabilized Zirconia was irradiated with Xe2+ and Xe3+ ions at 320 and 450 keV over a range of doses from 1013 to 1016 ions/cm2. Damage appears as a 150 nm surface layer with a dense dislocation network. The X-ray diffraction pattern shows an increasing lattice expansion with increasing dose that reaches a saturation point. Ion irradiation increases the surface conductance of the material; this effect is removed with certain post-treatments. Preliminary isotope depth profiling indicates enhanced ion diffusion in the damaged layer.

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