An identification scheme of grain boundaries and construction of a grain boundary energy database

2011 ◽  
Vol 64 (12) ◽  
pp. 1152-1155 ◽  
Author(s):  
Hyun-Kyu Kim ◽  
Won-Seok Ko ◽  
Hyuk-Joong Lee ◽  
Seong Gyoon Kim ◽  
Byeong-Joo Lee
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Boundary Energy ◽  
Grain Boundary Energy ◽  
Identification Scheme

Effect of Grain Boundary Energy Anisotropy on Faceting and Migration of Low Angle Grain Boundaries

2014 ◽  
Vol 783-786 ◽  
pp. 1634-1639
Author(s):  
Dmitri A. Molodov ◽  
Jann Erik Brandenburg ◽  
Luis Antonio Barrales-Mora ◽  
Günter Gottstein
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Elevated Temperatures ◽  
Boundary Energy ◽  
Migration Behavior ◽  
Grain Boundary Energy ◽  
Contrast Imaging ◽  
Orientation Contrast ◽  
And Migration ◽  
Twist Boundaries

The faceting and migration behavior of low angle <100> grain boundaries in high purity aluminum bicrystals was investigated. In-situ technique based on orientation contrast imaging was applied. In contrast to the pure tilt boundaries, which remained straight/flat and immobile during annealing at elevated temperatures, mixed tilt-twist boundaries readily assumed a curved shape and steadily moved under the capillary force. Computational analysis revealed that this behavior is due to the inclinational anisotropy of grain boundary energy, which in turn depends on boundary geometry – the energy of pure tilt low angle <100> boundaries is anisotropic, whereas that of mixed tilt-twist boundaries isotropic with respect to boundary inclination.

Grain-Boundary Energy and Grain-Boundary Groove Angles in Ice

1972 ◽  
Vol 11 (62) ◽  
pp. 265-277 ◽  
Author(s):  
Shigenao Suzuki ◽  
Daisuke Kuroiwa
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Boundary Energy ◽  
Grain Boundary Energy ◽  
Boundary Groove ◽  
Grain Boundary Grooves

Abstract Relative grain-boundary energies in ice were measured as a function of mismatch angles made by the c-axes or a-axes in grains, using ice specimens having triple grain boundaries. It was found that the Read–Shockley equation for grain-boundary energy was valid for grain boundaries tilted between 0° and 15°. Angles of the solid–vapour grain-boundary groove in ice were measured by the use of micro-interferometry at grain-boundary grooves covered with extremely thin metalic foil. The data were compared with those measured by a silvered replica of grain-boundary grooves.

Survey of Grain Boundary Energies in Four Elemental Metals

2012 ◽  
Vol 715-716 ◽  
pp. 179-179
Author(s):  
David L. Olmsted ◽  
Elizabeth A. Holm ◽  
Stephen M. Foiles
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Energy Minimization ◽  
Boundary Energy ◽  
Atomic Scale ◽  
Energy Structure ◽  
Grain Boundary Energy ◽  
Fcc Metals ◽  
Composition And Structure ◽  
Boundary Properties

Grain boundary properties depend on both composition and structure. To test the relative contributions of composition and structure to the grain boundary energy, we calculated the energy of 388 grain boundaries in four elemental, fcc metals: Ni, Al, Au and Cu. We constructed atomic-scale bicrystals of each boundary and subjected them to a rigorous energy minimization process to determine the lowest energy structure. Typically, several thousand boundary configurations were examined for each boundary in each element.

Effect of inclination dependence of grain boundary energy on the mobility of tilt and non-tilt low-angle grain boundaries

2013 ◽  
Vol 68 (12) ◽  
pp. 980-983 ◽  
Author(s):  
J.-E. Brandenburg ◽  
L.A. Barrales-Mora ◽  
D.A. Molodov ◽  
G. Gottstein
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Boundary Energy ◽  
Grain Boundary Energy

Preferred inclinations of grain boundaries in epitaxially grown bicrystalline thin films of gold

1978 ◽  
Vol 36 (1) ◽  
pp. 434-435
Author(s):  
F. Cosandey ◽  
Y. Komem ◽  
C. L. Bauer
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Boundary Energy ◽  
Boundary Plane ◽  
Boundary Structure ◽  
Structural Elements ◽  
Grain Boundary Energy ◽  
Transmission Electron ◽  
A New Technique ◽  
Misorientation Of Grains

Energy and concomitant structure of grain boundaries are related to inclination of the boundary plane as well as misorientation of grains defining the boundary. Although increasing information is becoming available on variation of grain boundary energy with misorientation, still relatively little is known about variation of grain boundary energy with inclination. The purpose of this research is to examine preferred inclinations of preselected grain boundaries in gold by transmission electron microscopy (TEM) in order to identify principal structural elements and to relate these elements to the energy of special grain boundary configurations.Grain boundaries examined in this research are produced by a new technique involving vapor deposition of gold on common (001) surfaces of bicrystalline substrates of NaCl, characterized by preselected rotation about a common [001] axis, and subsequent epitaxial growth to form a bicrystalline thin film. These films are then removed from their substrates and examined by TEM. The principal advantage of this technique is that the grain boundary is formed during the deposition and growth process, thus resulting in a more perfect boundary structure while eliminating necessity of a separate bonding operation.

Inclination dependence of grain boundary energy and its impact on the faceting and kinetics of tilt grain boundaries in aluminum

2008 ◽  
Vol 56 (18) ◽  
pp. 4998-5011 ◽  
Author(s):  
D.M. Kirch ◽  
E. Jannot ◽  
L.A. Barrales-Mora ◽  
D.A. Molodov ◽  
G. Gottstein
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Boundary Energy ◽  
Grain Boundary Energy ◽  
Kinetics Of

Computer simulation on surfaces and [001] symmetric tilt grain boundaries in Ni, Al, and Ni3Al

1989 ◽  
Vol 4 (1) ◽  
pp. 62-77 ◽  
Author(s):  
S. P. Chen ◽  
D. J. Srolovitz ◽  
A. F. Voter
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Structural Unit ◽  
Boundary Energy ◽  
Boundary Structure ◽  
Grain Boundary Energy ◽  
Local Composition ◽  
Embedded Atom ◽  
Grain Boundary Structure ◽  
Unit Model

We have used “local volume” (embedded atom) type potentials to study the surfaces and grain boundaries of Ni, Al, and Ni3Al. The simulations show that with appropriately fit potentials, the surface and grain boundary structure can be realistically calculated. The surface rippling and relaxation show good agreement with experiments. The energies of most surfaces and grain boundaries also agree with existing data. The structural unit model for grain boundaries in Ni3Al shows the same generic units as in pure metals, but with large variations due to distortions and multiplicity. The utility of the structural unit model is thus more limited for alloys. The grain boundary energies were found to be the highest for Al-rich Ni3Al grain boundaries, and depend significantly on the local composition of the grain boundary. The cusps in the grain boundary energy as a function of misorientation angle are different for different grain boundary stoichiometries. The Ni3Al grain boundaries have approximately the same grain boundary energy and cohesive energy as that of Ni.

scholarly journals Nanoscale mapping of the electron density at Al grain boundaries and correlation with grain-boundary energy

2019 ◽  
Vol 3 (5) ◽  
Author(s):  
Proloy Nandi ◽  
Xiahan Sang ◽  
Eric R. Hoglund ◽  
Raymond R. Unocic ◽  
Dmitri A. Molodov ◽  
...  
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Electron Density ◽  
Boundary Energy ◽  
Grain Boundary Energy

scholarly journals Structure and Behaviour of Grain Boundaries in Polycrystalline Ice

1978 ◽  
Vol 21 (85) ◽  
pp. 589-605
Author(s):  
Akira Higashi
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Moving Boundary ◽  
Boundary Energy ◽  
Coincidence Site Lattice ◽  
Geometrical Model ◽  
Grain Boundary Energy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Polycrystalline Ice

AbstractRecent progress in studies of the structure and behaviour of grain boundaries in ice are reviewed. As a lattice geometrical model of the boundary, the coincidence-site lattice (CSL) model is considered for ice crystals. Some evidence of the validity of this model is presented through observations of special shapes of natural snow, results of grain-boundary energy measurements, and direct microscopic observations of boundaries by X-ray diffraction topography. Although methods of measurement of grain-boundary energy have been developed recently, results are still not adequate to be analysed in terms of real energetics for comparison with models of atomic bonding. Modern methods of observing grain boundaries in ice using X-ray diffraction topography are described. Observations of migrating boundaries have revealed that faceting along most closely packed CSL points impede the migration of the CSL boundaries whilst increased numbers of steps among facets with boundaries of other kinds enhance it. The mobility of a fast-moving boundary has been determined to be of the order of 10-10 cm3 dyn-1 s-1 (10-11 m3 N-1 s-1) either in the case when the driving force is the capillary force due to the boundary energy or when it is the stored energy of dislocations.

Formation And Stability Of Nanocrystalline Nb-Cu Alloys

1991 ◽  
Vol 238 ◽  
Author(s):  
Yoshio R. Abe ◽  
J. C. Holzer ◽  
W. L. Johnson
Keyword(s):  
Differential Scanning Calorimetry ◽  
Grain Boundary ◽  
Grain Boundaries ◽  
Grain Growth ◽  
Thermal Activation ◽  
Boundary Energy ◽  
Grain Boundary Energy ◽  
Scanning Calorimetry ◽  
Second Stage ◽  
Cu Alloys

ABSTRACTNanocrystalline Nb100−xCux (0 ≤ x ≤ 30) alloys of 8 – 25 nm grain size are synthesized with the mechanical alloying technique. Differential scanning calorimetry reveals two separate stages of grain growth. In the first stage, the grain growth is associated with migration of solute Cu atoms to grain boundaries. Grain growth stops as the grain boundaries are saturated with Cu. The second reaction takes place either when the threshold for the nucleation of an Fcc Cu phase in the grain boundary is overcome by thermal activation, or when segregating Cu atoms in the grain boundary are driven by diffusion to the growing Cu grains, and the Cu concentration in the grain boundary drops. This increases the grain boundary energy, and initiates a second stage of rapid grain growth.

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