Observation of electromigration in a Cu thin line by in situ coherent x-ray diffraction microscopy

In this paper the authors describe a technique based on synchrotron x-ray diffraction which has been used to produce full 3D grain maps (both grain shapes and orientations) in annealed aluminium alloy and stainless steel samples containing around 500 grains. The procedure is termed diffraction contrast tomography (DCT), reflecting its similarities with conventional absorption contrast tomography. It is an extension of the 3D X-ray diffraction microscopy (3DXRD) concept, and has been developed in collaboration with its inventors. The specimen is illuminated using a monochromatic synchrotron x-ray beam, and grains imaged using the extinction contrast that appears in the transmitted beam when grains are aligned in the diffraction condition during rotation of the sample. The beams of radiation diffracted by the grains are captured simultaneously on the same detector as the direct beam image. The combination of diffraction and extinction information aids the grain indexing operation, in which pairs of diffraction and extinction images are assigned to grain sets. 3D grain shapes are determined by algebraic reconstruction from the limited number of extinction projections, while crystallographic orientation is found from the diffraction geometry. The non-destructive nature of the technique allows for in-situ studies of mapped samples. Research is in progress to extend the technique to allow the determination of the elastic strain and stress tensors on a grain-by-grain basis.

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DART: a robust algorithm for fast reconstruction of three-dimensional grain maps

Journal of Applied Crystallography ◽

10.1107/s0021889810034114 ◽

2010 ◽

Vol 43 (6) ◽

pp. 1464-1473 ◽

Cited By ~ 23

Author(s):

K. J. Batenburg ◽

J. Sijbers ◽

H. F. Poulsen ◽

E. Knudsen

Keyword(s):

Three Dimensional ◽

Reconstruction Technique ◽

X Ray Diffraction ◽

X Ray ◽

Iterative Reconstruction Technique ◽

Discrete Nature ◽

Fast Reconstruction ◽

Microscopy Data ◽

Diffraction Microscopy

A novel algorithm is introduced for fast and nondestructive reconstruction of grain maps from X-ray diffraction data. The discrete algebraic reconstruction technique (DART) takes advantage of the intrinsic discrete nature of grain maps, while being based on iterative algebraic methods known from classical tomography. To test the properties of the algorithm, three-dimensional X-ray diffraction microscopy data are simulated and reconstructed with DART as well as by a conventional iterative technique, namely SIRT (simultaneous iterative reconstruction technique). For 100 × 100 pixel reconstructions and moderate noise levels, DART is shown to generate essentially perfect two-dimensional grain maps for as few as three projections per grain with running times on a PC in the range of less than a second. This is seen as opening up the possibility for fast reconstructions in connection within situstudies.

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Growth Rate Distributions during Recrystallization of Copper

Materials Science Forum ◽

10.4028/www.scientific.net/msf.467-470.197 ◽

2004 ◽

Vol 467-470 ◽

pp. 197-202 ◽

Cited By ~ 2

Author(s):

R.A. Vandermeer ◽

Erik M. Lauridsen ◽

Dorte Juul Jensen

Keyword(s):

Pure Copper ◽

Activation Energies ◽

Individual Characteristics ◽

X Ray Diffraction ◽

X Ray ◽

Wide Range ◽

Apparent Activation Energies ◽

Diffraction Microscopy ◽

Purity Copper

New 3D X-ray diffraction microscopy (3DXRD) experiments on recrystallizing bulk grains that nucleated and grew in a 92% cold deformed pure copper during in situ annealing at both 150° C and 160° C are described. Nucleation times, growth velocities and apparent activation energies were determined for each grain. A wide range of apparent activation energies was observed but the average of 123 kJ/mol agreed well with earlier recrystallization experiments on a similar purity copper. It was clear that each recrystallized grain had its own individual characteristics; the grains do not all behave alike as various models would suppose.

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Micro-scale dissolution seams mobilise carbon in deep-sea limestones

Communications Earth & Environment ◽

10.1038/s43247-021-00257-w ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Christoph E. Schrank ◽

Michael M. W. Jones ◽

Cameron M. Kewish ◽

Grant A. van Riessen ◽

Kathryn E. Elphick ◽

...

Keyword(s):

Carbon Cycle ◽

Deep Sea ◽

Carbon Sink ◽

Bulk Sample ◽

X Ray Diffraction ◽

X Ray ◽

Calcite Cement ◽

Diffraction Microscopy

AbstractMeasuring the amount of carbon captured in deep-sea limestones is fundamental to understanding the long-term carbon cycle because pelagic limestones represent Earth’s largest carbon sink since the mid-Mesozoic. However, their contribution to the long-term carbon cycle is poorly quantified. Here, we use X-ray fluorescence and scanning X-ray diffraction microscopy for high-resolution chemical and structural analysis of pelagic limestone from the Paleocene Kaiwhata Formation in New Zealand. We identify densely packed diagenetic micro-dissolution seams that are invisible to light and electron-beam microscopes in most cases. Mass-balance calculations indicate that individual seams remove ~50% of the calcite mud matrix while their bulk-sample carbon loss adds up to ~10%. The liberated carbon is trapped in situ as calcite cement or returned to the ocean during physical compaction or soft-sediment deformation. We suggest micro-dissolution structures may play an important role in the long-term carbon cycle by modulating carbon exchange between the geosphere and hydrosphere.

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The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071107 ◽

1973 ◽

Vol 31 ◽

pp. 132-133 ◽

Cited By ~ 1

Author(s):

R. E. Herfert

Keyword(s):

Surface Characterization ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Depth Of Penetration ◽

X Ray ◽

The Past ◽

Transmission Electron ◽

Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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