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

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Motion of Grain Boundaries: Experiments on Bicrystals

Diffusion Foundations ◽

10.4028/www.scientific.net/df.5.247 ◽

2015 ◽

Vol 5 ◽

pp. 247-271

Author(s):

Dmitri A. Molodov

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Misorientation Angle ◽

Elevated Temperatures ◽

Activation Enthalpy ◽

Boundary Migration ◽

Boundary Energy ◽

Boundary Plane ◽

Migration Behavior ◽

Twist Boundaries

Recent research on grain boundary migration is reviewed. Novel in-situ measuring techniques based on orientation contrast imaging and the experimental results obtained on specially grown bicrystals are presented. Particularly, the investigated faceting and migration behavior of low angle grain boundaries under the curvature force in aluminum bicrystals was addressed. 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 migration of planar grain boundaries induced by a magnetic field was measured in bismuth and zinc bicrystals. Various structurally different boundaries were investigated. The results revealed that grain boundary mobility essentially depends on the misorientation angle and the inclination of the boundary plane. Stress driven boundary migration in aluminium bicrystals was observed to be coupled to a tangential translation of the grains. The activation enthalpy of high angle boundary migration was found to vary non-monotonously with misorientation angle, whereas for low angle boundaries the migration activation enthalpy was virtually the same. The motion of the mixed tilt-twist boundaries under stress was observed to be accompanied by both the translation of adjacent grains parallel to the boundary plane and their rotation around the boundary plane normal.

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

Journal of Glaciology ◽

10.1017/s0022143000022255 ◽

1972 ◽

Vol 11 (62) ◽

pp. 265-277 ◽

Cited By ~ 12

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.

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Survey of Grain Boundary Energies in Four Elemental Metals

Materials Science Forum ◽

10.4028/www.scientific.net/msf.715-716.179 ◽

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.

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

Scripta Materialia ◽

10.1016/j.scriptamat.2013.02.054 ◽

2013 ◽

Vol 68 (12) ◽

pp. 980-983 ◽

Cited By ~ 16

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

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

Scripta Materialia ◽

10.1016/j.scriptamat.2011.03.020 ◽

2011 ◽

Vol 64 (12) ◽

pp. 1152-1155 ◽

Cited By ~ 35

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

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

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109318 ◽

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.

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

Acta Materialia ◽

10.1016/j.actamat.2008.06.017 ◽

2008 ◽

Vol 56 (18) ◽

pp. 4998-5011 ◽

Cited By ~ 48

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

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Structural Dependence of Grain Boundary Energy in Fe-Based Polycrystals Identified by OIM Measurements

Materials Science Forum ◽

10.4028/www.scientific.net/msf.550.411 ◽

2007 ◽

Vol 550 ◽

pp. 411-416

Author(s):

Patricia Gobernado ◽

Leo Kestens

Keyword(s):

Grain Boundary ◽

Boundary Energy ◽

Initial Boundary ◽

Geometrical Configuration ◽

Grain Boundary Energy ◽

Triple Junctions ◽

High Angle ◽

Orientation Contrast ◽

Contrast Microscopy ◽

Two Parameter

The (relative) grain boundary energy of random high angle boundaries has been measured in several Fe-based polycrystals. Crystallographic data obtained by orientation contrast microscopy (OIM) are combined with the geometrical configuration of grain boundaries at triple junctions. A two-parameter representation of the relative grain boundary energy in terms of misorientation angle and misorientation axis is presented. In the applied procedure a variation of the energy values assigned to one boundary was observed depending on the triangulation path chosen by the operator to connect the arbitrary initial boundary with the boundary under consideration. Results show no evidence of correspondence between the observed energy cusps and the presence of CSL boundaries.

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

Journal of Materials Research ◽

10.1557/jmr.1989.0062 ◽

1989 ◽

Vol 4 (1) ◽

pp. 62-77 ◽

Cited By ~ 151

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.

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