Three-beam X-ray diffraction – profile analysis

An original functional description of the intensity perturbation of the two-beam diffracted power caused by an interfering three-beam interaction has been developed. By using this approach in the analysis of measured three-beam profiles of α-oxalic acid dihydrate, parameters related to the Darwin mosaic model are refined. The final results indicate an anisotropy in both the mean domain size, measured along the secondary beam, and the block orientation, measured as the angular spread in the location of the three-beam point. The presented method relies on a procedure for merging the contributions to the perturbation originating from dynamical (coherent) and kinematical (incoherent) scattering processes.

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An Evaluation of Deconvolution Techniques in X-ray Profile Broadening Analysis and the Application of the Maximum Entropy Method to Alumina Data

Advances in X-ray Analysis ◽

10.1154/s0376030800018036 ◽

1994 ◽

Vol 38 ◽

pp. 387-395 ◽

Cited By ~ 1

Author(s):

Walter Kalceff ◽

Nicholas Armstrong ◽

James P. Cline

Keyword(s):

Maximum Entropy ◽

Maximum Entropy Method ◽

Profile Analysis ◽

Domain Size ◽

Entropy Method ◽

X Ray Diffraction ◽

Profile Function ◽

Diffraction Profile ◽

X Ray ◽

Deconvolution Techniques

Abstract This paper reviews several procedures for the removal of instrumental contributions from measured x-ray diffraction profiles, including: direct convolution, unconstrained and constrained deconvolution, an iterative technique, and a maximum entropy method (MEM) which we have adapted to x-ray diffraction profile analysis. Decorevolutions using the maximum entropy approach were found to be the most robust with simulated profiles which included Poisson-distributed noise and uncertainties in the instrument profile function (IPF). The MEM procedure is illustrated by application to the analysis for domain size and microstrain carried out on the four calcined α-alumina candidate materials for Standard Reference Material (SRM) 676 (a quantitative analysis standard for I/Ic determinations), along with the certified material. Williamson-Hall plots of these data were problematic with respect to interpretation of the microstrain, indicating that the line profile standard, SRM 660 (LaB6), exhibits a small amount of strain broadening, particularly at high 2θ angle. The domain sizes for all but one of the test materials were much smaller than the crystallite (particle) size; indicating the presence of low angle grain boundaries.

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X-Ray Diffraction Profile Analysis for Characterizing Isothermal Aging Behavior of M250 Grade Maraging Steel

Metallurgical and Materials Transactions A ◽

10.1007/s11661-008-9550-1 ◽

2008 ◽

Vol 39 (8) ◽

pp. 1978-1984 ◽

Cited By ~ 8

Author(s):

S. Mahadevan ◽

T. Jayakumar ◽

B.P.C. Rao ◽

Anish Kumar ◽

K.V. Rajkumar ◽

...

Keyword(s):

Maraging Steel ◽

Isothermal Aging ◽

Profile Analysis ◽

X Ray Diffraction ◽

Aging Behavior ◽

Diffraction Profile ◽

X Ray

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Correction of X-ray Diffraction Profiles Measured by PSPC System

Advances in X-ray Analysis ◽

10.1154/s0376030800019819 ◽

1989 ◽

Vol 33 ◽

pp. 397-402 ◽

Cited By ~ 1

Author(s):

Shin'ichi Ohya ◽

Yasuo Yoshioka

Keyword(s):

Profile Analysis ◽

X Rays ◽

X Ray Diffraction ◽

Diffraction Profile ◽

X Ray ◽

Geometrical Problem ◽

Straight Line ◽

Background Line ◽

Diffraction Angle ◽

Position Sensitive

When an x-ray diffraction profile Is measured for stress analysis or profile analysis by the use of a linear (straight line) position sensitive proportional counter (PSPC) , a convex-type background line is obtained because of the geometrical problem and the absorption of x-rays. Such phenomenon is remarkable when a wide angular range is set on a linear PSPC and it is, in particular, necessary to correct with a straight background for accurate measurement of diffraction angle or half-value breadth of the broadened diffraction profile.

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Formation process of nanocrystalline materials from x-ray diffraction profile analysis: Application to platinum catalysts

Journal of Applied Physics ◽

10.1063/1.1453495 ◽

2002 ◽

Vol 91 (7) ◽

pp. 4556-4561 ◽

Cited By ~ 43

Author(s):

P. Ascarelli ◽

V. Contini ◽

R. Giorgi

Keyword(s):

Formation Process ◽

Nanocrystalline Materials ◽

Profile Analysis ◽

Platinum Catalysts ◽

X Ray Diffraction ◽

Diffraction Profile ◽

X Ray ◽

Analysis Application

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Dislocation Density of Plastically Deformed Oxygen-Free Copper

Materials Science Forum ◽

10.4028/www.scientific.net/msf.905.60 ◽

2017 ◽

Vol 905 ◽

pp. 60-65

Author(s):

Mutsumi Sano ◽

Sunao Takahashi ◽

Atsuo Watanabe ◽

Ayumi Shiro ◽

Takahisa Shobu

Keyword(s):

Synchrotron Radiation ◽

Dislocation Density ◽

Profile Analysis ◽

Plastic Strains ◽

X Ray Diffraction ◽

Diffraction Profile ◽

X Ray ◽

Dislocation Densities

The dislocation density of plastically deformed oxygen free copper (OFC) was evaluated by X-ray diffraction profile analysis with synchrotron radiation. The modified Williamson-Hall and modified Warren-Averbach methods were applied to the analysis. The dislocation densities of OFC samples with compressive plastic strains of 1 % and 4 % were 5.1×1014 m-2 and 9.2×1014 m-2, respectively.

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