The Influence of Anisotropic Grain Boundary Energy on Triple Junction Morphology and Grain Growth

MRS Proceedings ◽

10.1557/proc-529-9 ◽

1998 ◽

Vol 529 ◽

Author(s):

Alexander H. King

Keyword(s):

Grain Boundary ◽

Triple Junction ◽

Driving Force ◽

Boundary Migration ◽

Boundary Energy ◽

Dihedral Angles ◽

Grain Boundary Migration ◽

Grain Boundary Energy ◽

Boundary Curvature ◽

Energy Anisotropy

AbstractWe consider some examples of triple junction equilibration in the presence of grain boundary energy anisotropy. It is shown that the presence of one or two cusp-trapped grain boundaries can reduce the restrictions upon the dihedral angles formed with the remaining (isotropic) boundaries This allows for a reduction in the average grain boundary curvature, and thus in the driving force for grain boundary migration.

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Extraction of Grain Boundary Energies from Triple Junction Geometry

Microscopy and Microanalysis ◽

10.1017/s1431927600014471 ◽

1999 ◽

Vol 5 (S2) ◽

pp. 230-231

Author(s):

A. D. Rollett ◽

C.-C. Yang ◽

W. W. Mullins ◽

B. L. Adams ◽

C. T. Wu ◽

...

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Triple Junction ◽

Preliminary Analysis ◽

Boundary Energy ◽

Orientation Imaging Microscopy ◽

Dihedral Angles ◽

Grain Boundary Energy ◽

Boundary Character ◽

Junction Geometry

Measurement of the geometry of triple junctions between grain boundaries in polycrystalline materials is used to generate large sets of dihedral angles from which maps of the grain boundary energy are extracted. A preliminary analysis has been performed for samples of magnesia and aluminum based on a three-parameter description of grain boundaries. An extended form of orientation imaging microscopy (OIM) was used to measure both triple junction geometry via image analysis in the SEM and local grain orientation via electron back scatter diffraction. Serial sectioning with registry of both in-plane images and successive sections characterizes triple junction tangents from which true dihedral angles are calculated. If there is local equilibrium at each triple junction, we may apply Herring's relation. By limiting grain boundary character to a (three parameter) specification of misorientation for the preliminary analysis, we can neglect the torque terms and apply the sine law to the three boundaries. This provides two independent relations per triple junction between grain boundary energies and dihedral angles. By discretizing the misorientation and employing multiscale statistical analysis on large data sets, (relative) grain boundary energy as a function of boundary character can be extracted from triple junction geometry. The results are discussed with respect to current understanding of grain boundary structure based on their crystallography. The results suggest that a three parameter characterization of grain boundaries (lattice disorientation) is not an adequate description of boundary character. A full analysis including torque terms and a five parameter boundary description is under development.

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STUDY OF THE GRAIN BOUNDARY MIGRATION IN A TRICRISTAL PURE ICE WITH BUBBLES

Anales AFA ◽

10.31527/analesafa.2019.30.3.47 ◽

2019 ◽

Vol 30 (3) ◽

pp. 47-51

Author(s):

P.I. Achával ◽

C. L. Di Prinzio

Keyword(s):

Monte Carlo ◽

Grain Boundary ◽

Numerical Simulations ◽

Triple Junction ◽

Boundary Migration ◽

Optical Microscope ◽

Physical Parameters ◽

Grain Boundary Migration

In this paper the migration of a grain triple junction in apure ice sample with bubbles at -5°C was studied for almost 3hs. This allowed tracking the progress of the Grain Boundary (BG) and its interaction with the bubbles. The evolution of the grain triple junction was recorded from successive photographs obtained witha LEICA® optical microscope. Simultaneously, numerical simulations were carried out using Monte Carlo to obtain some physical parameters characteristic of the BG migration on ice.

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