Apparent Anomalous Absorption and Image Matching

Visual matching of experimental and theoretical electron micrographs can be used to determine the apparent anomalous absorption constant. The method has been applied to a copper-silicon (8 at. % Si) alloy by matching experimental and theoretical images of a Shockley partial dislocation and the main and subsidiary fringes of the associated stacking fault. The value of 0�067 which is obtained is considerably less than the value of 0�1 usually assumed for metals and alloys. In foils approximately 3611 thick details of the image are very sensitive to the value ofthe anomalous absorption constant and the value of 0�1 is inadequate for image matching. However, in foils approximately 6611thick the general topological features of an image are little altered by varying the anomalous absorption constant over a wide range and the approximate value of O� 1 is adequate for image matching.

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Shrinking stacking fault through glide of the Shockley partial dislocation in hard-sphere crystal under gravity

Molecular Physics ◽

10.1080/00268970701348725 ◽

2007 ◽

Vol 105 (10) ◽

pp. 1377-1383 ◽

Cited By ~ 15

Author(s):

Atsushi Mori ◽

Yoshihisa Suzuki ◽

Shin-Ichiro Yanagiya ◽

Tsutomu Sawada ◽

Kensaku Ito

Keyword(s):

Hard Sphere ◽

Partial Dislocation ◽

Stacking Fault ◽

Shockley Partial Dislocation ◽

Shockley Partial

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Photoluminescence Imaging and Wavelength Analysis of Basal Plane Frank-Type Defects in 4H-SiC Epilayers

Materials Science Forum ◽

10.4028/www.scientific.net/msf.725.15 ◽

2012 ◽

Vol 725 ◽

pp. 15-18 ◽

Cited By ~ 4

Author(s):

Isaho Kamata ◽

Xuan Zhang ◽

Hidekazu Tsuchida

Keyword(s):

Basal Plane ◽

Partial Dislocation ◽

Near Infrared ◽

Stacking Fault ◽

Profile Measurement ◽

Infrared Wavelength ◽

Visible Light Range ◽

Wide Range ◽

Fault Region ◽

Narrow Emission

Frank-type defects on a basal plane have been investigated using photoluminescence (PL) imaging microscopy and wavelength profile measurement. A wide range of emission in the near-infrared wavelength was observed from a Frank partial dislocation at the edge of the defect, while a narrow emission at around the visible light range was obtained from a stacking fault region. The emissions from a stacking fault region of three kinds of basal plane Frank-type defects were confirmed to have different wavelengths depending on their stacking structures.

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Computer Simulation of Creation of Dislocations in Copper Small Crystals

MRS Proceedings ◽

10.1557/proc-319-319 ◽

1993 ◽

Vol 319 ◽

Author(s):

H. Tanaka ◽

Masao Doyama

Keyword(s):

Molecular Dynamics ◽

Computer Simulation ◽

Partial Dislocation ◽

Stacking Fault ◽

Shockley Partial Dislocation ◽

Shockley Partial ◽

Small Crystals ◽

The Creation

AbstractDislocations were created near the center of the surface (101) of copper small crystals whose surfaces are (111), (111), (101), (101), (121), and (121) by use of n-body atom potentials and molecular dynamics. At first, a Heidenreich-Shockley partial dislocation was created., As the partial dislocation proceeds, the partial dislocation and the surface was connected with a stacking fault until the next Heidenreich-Shockley partial dislocation was created at the surface.Just before the creation of a partial dislocation the stress was the highest.

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Computer Simulation of Creation of Dislocations in Copper Small Crystals

MRS Proceedings ◽

10.1557/proc-319-311 ◽

1993 ◽

Vol 319 ◽

Author(s):

H. Tanaka ◽

Masao Doyama

Keyword(s):

Molecular Dynamics ◽

Computer Simulation ◽

Partial Dislocation ◽

Stacking Fault ◽

Shockley Partial Dislocation ◽

Shockley Partial ◽

Small Crystals ◽

The Creation

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Creation and Motion of Edge Dislocations in Copper Single Crystals

MRS Proceedings ◽

10.1557/proc-505-279 ◽

1997 ◽

Vol 505 ◽

Author(s):

Masaodoyama ◽

Yoshiaki Kogure ◽

Tadatoshi Nozaki

Keyword(s):

Molecular Dynamics ◽

Single Crystals ◽

Partial Dislocation ◽

Stacking Fault ◽

Shockley Partial Dislocation ◽

Shockley Partial ◽

Small Crystals ◽

The Creation ◽

Copper Single Crystals ◽

Edge Dislocations

ABSTRACTDislocations were created near the center of the surface (110) of copper small crystals whose surfaces are (111), (111), (110), (110), (112), and (112) by use of n-body atom potentials and molecular dynamics. At first, a Heidenreich-Shockley partial dislocation was created. As the partial dislocation proceeds, the partial dislocation and the surface was connected with a stacking fault until the next Heidenreich-Shockley partial dislocation was created at the surface.Just before the creation of a partial dislocation the stress was the highest. For larger crystals, forming a step on (110) plane was not enough and a shear was necessary to move dislocations.

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Correlation of Grain Size, Stacking Fault Energy, and Texture in Cu-Al Alloys Deformed under Simulated Rolling Conditions

Advances in Materials Science and Engineering ◽

10.1155/2015/953130 ◽

2015 ◽

Vol 2015 ◽

pp. 1-12 ◽

Cited By ~ 5

Author(s):

Ehab A. El-Danaf ◽

Mahmoud S. Soliman ◽

Ayman A. Al-Mutlaq

Keyword(s):

Grain Size ◽

Strain Hardening ◽

Mechanical Twinning ◽

Al Alloys ◽

Stacking Fault ◽

Stacking Fault Energy ◽

Wide Range ◽

Orientation Density ◽

Pure Cu ◽

Strain Hardening Rate

The effect of grain size and stacking fault energy (SFE) on the strain hardening rate behavior under plane strain compression (PSC) is investigated for pure Cu and binary Cu-Al alloys containing 1, 2, 4.7, and 7 wt. % Al. The alloys studied have a wide range of SFE from a low SFE of 4.5 mJm−2for Cu-7Al to a medium SFE of 78 mJm−2for pure Cu. A series of PSC tests have been conducted on these alloys for three average grain sizes of ~15, 70, and 250 μm. Strain hardening rate curves were obtained and a criterion relating twinning stress to grain size is established. It is concluded that the stress required for twinning initiation decreases with increasing grain size. Low values of SFE have an indirect influence on twinning stress by increasing the strain hardening rate which is reflected in building up the critical dislocation density needed to initiate mechanical twinning. A study on the effect of grain size on the intensity of the brass texture component for the low SFE alloys has revealed the reduction of the orientation density of that component with increasing grain size.

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Shockley Partial Dislocation-Induced Self-Rectified 1D Hydrogen Evolution Photocatalyst

ACS Applied Materials & Interfaces ◽

10.1021/acsami.9b03465 ◽

2019 ◽

Vol 11 (22) ◽

pp. 20521-20527 ◽

Cited By ~ 6

Author(s):

Zhonghui Han ◽

Weizhao Hong ◽

Weinan Xing ◽

Yidong Hu ◽

Yansong Zhou ◽

...

Keyword(s):

Hydrogen Evolution ◽

Partial Dislocation ◽

Shockley Partial Dislocation ◽

Shockley Partial

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Interaction Between Lattice Dislocations and Grain Boundaries In Ordered Compounds

MRS Proceedings ◽

10.1557/proc-213-429 ◽

1990 ◽

Vol 213 ◽

Cited By ~ 1

Author(s):

B.J. Pestman ◽

J. Th. M. De Hosson ◽

V. Vitek ◽

F.W. Schapink

Keyword(s):

Shear Stress ◽

Grain Boundary ◽

Grain Boundaries ◽

Partial Dislocation ◽

Atomistic Simulations ◽

Many Body ◽

Shockley Partial Dislocation ◽

Screw Dislocations ◽

Applied Shear Stress ◽

Tilt Boundaries

ABSTRACTThe interaction of 1/2<1 1 0> screw dislocations with symmetric [1 1 0] tilt boundaries was investigated by atomistic simulations using many-body potentials representing ordered compounds. The calculations were performed with and without an applied shear stress. The observations were: absorption into the grain boundary, attraction of a lattice Shockley partial dislocation towards the grain boundary and transmission through the grain boundary under the influence of a shear stress. It was found that the interaction in ordered compounds shows similarities to the interaction in fcc.

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