The Change of X‐ray Diffraction Peak Width During
            in situ
            Conventional Sintering of Nanoscale Powders

ABSTRACTThe thermo-mechanical behavior of magnetron sputtered Fe polycrystalline films of thickness between 50 nm and 400 nm has been investigated. The state of stress has been determined by means of wafer curvature and X-ray diffraction (sin2ψ-method). Both methods are in good agreement for layers of thickness above 200 nm. For specimens of smaller layer thickness, however, the average stresses as measured by X-ray diffraction are systematically higher than those observed by wafer curvature experiments. The results can be interpreted in terms of differences in micro-strain (estimated using X-ray diffraction peak width analysis) and grain size as obtained by transmission and scanning electron microscopy. Thermal cycling experiments were performed between RT and 873 K. The effect of microstructure on thermo-mechanical properties was shown to be crucial.

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X-Ray Dynamical Diffraction in Powder Samples with Time-Dependent Particle Size Distributions

MRS Advances ◽

10.1557/adv.2019.445 ◽

2019 ◽

Vol 5 (29-30) ◽

pp. 1585-1591 ◽

Cited By ~ 1

Author(s):

Adriana Valério ◽

Sérgio L. Morelhão ◽

Alex J. Freitas Cabral ◽

Márcio M. Soares ◽

Cláudio M. R. Remédios

Keyword(s):

Particle Size ◽

Single Phase ◽

Diffraction Peak ◽

Time Dependent ◽

Peak Width ◽

Dynamical Diffraction ◽

X Ray ◽

Integrated Intensity ◽

Diffraction Effects

ABSTRACTIn situ X-ray diffraction is one of the most useful tools for studying a variety of processes, among which crystallization of nanoparticles where phase purity and size control are desired. Growth kinetics of a single phase can be completely resolved by proper analysis of the diffraction peaks as a function of time. The peak width provides a parameter for monitoring the time evolution of the particle size distribution (PSD), while the peak area (integrated intensity) is directly related to the whole diffracting volume of crystallized material in the sample. However, to precisely describe the growth kinetics in terms of nucleation and coarsening, the correlation between PSD parameters and diffraction peak widths has to be established in each particular study. Corrections in integrated intensity values for physical phenomena such as variation in atomic thermal vibrations and dynamical diffraction effects have also to be considered in certain cases. In this work, a general correlation between PSD median value and diffraction peak width is deduced, and a systematic procedure to resolve time-dependent lognormal PSDs from in situ XRD experiments is described in details. A procedure to correct the integrated intensities for dynamical diffraction effects is proposed. As a practical demonstration, this analytical procedure has been applied to the single-phase crystallization process of bismuth ferrite nanoparticles.

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Diffraction tomography and Rietveld refinement of a hydroxyapatite bone phantom

Journal of Applied Crystallography ◽

10.1107/s1600576715022633 ◽

2016 ◽

Vol 49 (1) ◽

pp. 103-109 ◽

Cited By ~ 8

Author(s):

S. Frølich ◽

H. Leemreize ◽

A. Jakus ◽

X. Xiao ◽

R. Shah ◽

...

Keyword(s):

Crystallite Size ◽

Rietveld Refinement ◽

Diffraction Peak ◽

Diffraction Tomography ◽

X Ray Diffraction ◽

X Ray ◽

Lattice Constants ◽

Model Sample ◽

Photon Source ◽

Diffraction Peak Width

A model sample consisting of two different hydroxyapatite (hAp) powders was used as a bone phantom to investigate the extent to which X-ray diffraction tomography could map differences in hAp lattice constants and crystallite size. The diffraction data were collected at beamline 1-ID, the Advanced Photon Source, using monochromatic 65 keV X-radiation, a 25 × 25 µm pinhole beam and translation/rotation data collection. The diffraction pattern was reconstructed for each volume element (voxel) in the sample, and Rietveld refinement was used to determine the hAp lattice constants. The crystallite size for each voxel was also determined from the 00.2 hAp diffraction peak width. The results clearly show that differences between hAp powders could be measured with diffraction tomography.

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SHOCK DEFORMATION STAGE CLASSIFICATION IN ORDINARY CHONDRITES USING IN SITU 2D XRD SIMPLE DIFFRACTION PEAK WIDTH MEASUREMENT OF OLIVINE

10.1130/abs/2019am-337942 ◽

2019 ◽

Author(s):

Alex N. Rupert ◽

◽

Phil J.A. McCausland ◽

Roberta L. Flemming

Keyword(s):

Diffraction Peak ◽

Peak Width ◽

Ordinary Chondrites ◽

Deformation Stage ◽

Shock Deformation ◽

Width Measurement ◽

Stage Classification ◽

Diffraction Peak Width

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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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