Grain Boundary Properties: Energy (L21) - Materials Science and ...

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Energy of High Angle Boundaries
• No universal theory exists to describe the energy of HAGBs.
• Based on a disordered atomic structure for general high angle
boundaries, we expect that the g.b. energy should be at a
maximum and approximately constant.
• Abundant experimental evidence for special boundaries at (a
small number) of certain orientations for which the atomic fit is
better than in general high angle g.b’s.
• Each special point (in misorientation space) expected to have a
cusp in energy, similar to zero-boundary case but with non-zero
energy at the bottom of the cusp.
• Atomistic simulations suggest that g.b. energy is (positively)
correlated with free volume at the interface.