Dislocation-Pairing Transitions in Hot Grain Boundaries

作者:Olmsted David L*; Buta Dorel; Adland Ari; Foiles Stephen M; Asta Mark; Karma Alain
来源:Physical Review Letters, 2011, 106(4): 046101.
DOI:10.1103/PhysRevLett.106.046101

摘要

We report the finding of a novel grain-boundary structural phase transition in both molecular-dynamics and phase-field-crystal simulations of classical models of bcc Fe. This transition is characterized by pairing of individual dislocations with mixed screw and edge components. We demonstrate that this type of transition is driven by a combination of factors including elastic softening, core interaction, and core disordering. At high homologous temperatures the occurrence of this transition is shown to prevent premelting at misorientation angles where it would otherwise be expected.

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