32545
2015
eng
188
201
2
50
article
Wiley-VCH Verlag GmbH & Co. KGaA
Weinheim
0
--
--
--
Euler angles and crystal symmetry
For the description of (single) crystal orientations, e.g. as measured by electron backscatter diffraction (EBSD) & X-ray diffraction (XRD), Euler angles are still generally used to import and export data. However, because of the lack of standard definitions for the unit cell reference settings and specimen axes, several transformation descriptions exist which produce different sets of Euler angles for the same orientation. There is also no recommended region within the minimal Euler orientation space into which orientations should be placed. This is the reason why different sets of Euler angles for the same orientation are generated by the available software packages for indexing EBSD patterns. These issues are reviewed and addressed.
The influence of crystal symmetry in form of chiral (enantiomorphic) groups is discussed, as well as how multiple, but symmetry-equivalent sets of Euler angles can be reduced in order to deliver a unique orientation description. The Euler coloring algorithms applied to EBSD map data is critically discussed. The specific case of cubic symmetry, especially the effect of the three-fold rotation on the Euler space is investigated in more detail for the highest-symmetric chiral group 432. Recommendations for standard settings of the unit cell to orthogonal coordinate system transformation are given which exploit inherent symmetry.
Crystal research and technology
35614
10.1002/crat.201400427
http://onlinelibrary.wiley.com/doi/10.1002/crat.201400427/full
0023-4753
1521-4079
0232-1300
Gert Nolze
eng
uncontrolled
EBSD
eng
uncontrolled
Crystal orientation
eng
uncontrolled
Pattern indexing
eng
uncontrolled
Subgroup relationship
5 Werkstofftechnik
5.1 Materialographie, Fraktographie und Alterung technischer Werkstoffe
Verlagsliteratur
Volltext-PDF im Netzwerk der BAM verfügbar ("Closed Access")
34477
2015
eng
1405
1419
48
article
Blackwell
Oxford
International Union of Crystallography
1
--
--
--
Kikuchi pattern analysis of noncentrosymmetric crystals
Different models of Kikuchi pattern formation are compared with respect to their applicability to noncentrosymmetric crystals, and the breakdown of Friedel's rule in experimental electron backscatter diffraction (EBSD) patterns is discussed. Different AIIIBV semiconductor materials are used to evaluate the resulting asymmetry of Kikuchi band profiles for polar lattice planes. By comparison with the characteristic etch pit morphology on a single-crystal surface, the polar character of the measured lattice planes can be assigned absolutely. The presented approach enables point-group-resolved orientation mapping, which goes beyond the commonly applied Laue group analysis in EBSD.
Journal of applied crystallography
37610
10.1107/S1600576715014016
0021-8898
1600-5767
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=Alerting&SrcApp=Alerting&DestApp=WOS&DestLinkType=FullRecord;UT=WOS:000362500100006
12.10.2015
Gert Nolze
C. Grosse
Aimo Winkelmann
eng
uncontrolled
EBSD
eng
uncontrolled
Pattern simulation
eng
uncontrolled
Point groups
eng
uncontrolled
Laue groups
eng
uncontrolled
Electron backscatter diffraction
eng
uncontrolled
Kikuchi patterns
eng
uncontrolled
Enantiomorphy; polarity
eng
uncontrolled
Friedel's rule
5 Werkstofftechnik
5.1 Materialographie, Fraktographie und Alterung technischer Werkstoffe
Verlagsliteratur
Volltext-PDF im Netzwerk der BAM verfügbar ("Closed Access")
34474
2015
eng
755
760
6
17
article
Wiley-VCH Verl.
Weinheim
1
--
--
--
A single-crystal co-base superalloy strengthened by gamma' precipitates: structure and mechanical properties
An experimental Co-base superalloy was designed from the Ni-base system by exchange of Ni and Co concentrations. The alloy consist of a Co-matrix (γ phase) strengthened by cuboidal precipitates Co3(Al,X) (γ' phase). The γ'-solvus temperature is 1?005?°C. [001] single crystals of this alloy were solidified and tested for tension at different temperatures up to 1?000?°C. It was found that the Co-base alloy has a much lower yield stress than a corresponding Ni-base alloy, but a much higher ductility. The partitioning behaviour of the alloying elements in the Co-base alloy and the deformation mechanisms were investigated by scanning and transmission electron microscopy.
Advanced engineering materials
37607
10.1002/adem.201500088
1438-1656
12.10.2015
N. Petrushin
K. Hvatzkiy
V. Gerasimov
T. Link
A. Epishin
Gert Nolze
G. Gerstein
eng
uncontrolled
Microstructure
eng
uncontrolled
Precipitation
eng
uncontrolled
Stress
5 Werkstofftechnik
5.1 Materialographie, Fraktographie und Alterung technischer Werkstoffe
Verlagsliteratur
Volltext-PDF im Netzwerk der BAM verfügbar ("Closed Access")
37787
2015
eng
50
58
156
article
0
--
--
--
Element-specific Kikuchi patterns of Rutile
The kinetic energy of keV electrons backscattered from a rutile (TiO2) surface depends measurably on the mass of the scattering atom. This makes it possible to determine separately the angular distribution of electrons backscattered elastically from either Ti or O. Diffraction effects of these backscattered electrons inside the rutile crystal lead to the formation of Kikuchi patterns. The element-resolved Kikuchi patterns of Ti and O differ characteristically, but each can be described fairly well in terms of the dynamical theory of diffraction. Qualitatively, much of the differences can be understood by considering the relative arrangement of the Ti and O atoms with respect to planes defined by the crystal lattice.
Ultramicroscopy
10.1016/j.ultramic.2015.04.018
0304-3991
M. Vos
Aimo Winkelmann
Gert Nolze
eng
uncontrolled
Electron Rutherford backscattering
eng
uncontrolled
TiO2
eng
uncontrolled
Kikuchi pattern
eng
uncontrolled
EBSD pattern
eng
uncontrolled
Simulation
Analytische Chemie
Ingenieurwissenschaften und zugeordnete Tätigkeiten
5 Werkstofftechnik
Material
Analytical Sciences
Verlagsliteratur
Volltext-PDF im Netzwerk der BAM verfügbar ("Closed Access")
5.0 Abteilungsleitung und andere
31384
2015
eng
58
63
149
article
Elsevier
New York, NY
1
--
--
--
Chirality determination of quartz crystals using electron backscatter diffraction
We demonstrate the determination of crystal chirality using electron backscatter diffraction (EBSD) in the scanning electron microscope. The chirality of a-quartz as a space-group-dependent property is verified via direct comparison of experimental diffraction features to simulations using the dynamical theory of electron diffraction.
Ultramicroscopy
34399
10.1016/j.ultramic.2014.11.013
0304-3991
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=Alerting&SrcApp=Alerting&DestApp=WOS&DestLinkType=FullRecord;UT=WOS:000348455100008
18.09.2014
Aimo Winkelmann
Gert Nolze
eng
uncontrolled
Electron backscatter diffraction
eng
uncontrolled
Kikuchi patterns
eng
uncontrolled
Chirality
eng
uncontrolled
Quartz
5 Werkstofftechnik
5.1 Materialographie, Fraktographie und Alterung technischer Werkstoffe
Verlagsliteratur
Volltext-PDF im Netzwerk der BAM verfügbar ("Closed Access")
32670
2015
eng
072101-1
072101-4
106
article
American Institute of Physics
Melville, NY
1
--
--
--
Point-group sensitive orientation mapping of non-centrosymmetric crystals
We demonstrate polarity-sensitive orientation mapping of non-centrosymmetric phases by Electron Backscatter Diffraction (EBSD). The method overcomes the restrictions of kinematic orientation determination by EBSD, which is limited to the centro-symmetric Laue-groups according to Friedel's rule. Using polycrystalline GaP as an example, we apply a quantitative pattern matching approach based on simulations using the dynamical theory of electron diffraction. This procedure results in a distinct assignment of the local orientation according to the non-centrosymmetric point group of the crystal structure under investigation.
Applied physics letters
35743
10.1063/1.4907938
0003-6951
1077-3118
02.03.2015
Aimo Winkelmann
Gert Nolze
eng
uncontrolled
Scanning electron microscopy
eng
uncontrolled
Electron backscatter diffraction
eng
uncontrolled
Orientation mapping
eng
uncontrolled
Non-centrosymmetric crystals
5 Werkstofftechnik
5.1 Materialographie, Fraktographie und Alterung technischer Werkstoffe
Verlagsliteratur
Volltext-PDF im Netzwerk der BAM verfügbar ("Closed Access")