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Incommensurate grain-boundary atomic structure.

ABSTRACT: Grain-boundary atomic structures of crystalline materials have long been believed to be commensurate with the crystal periodicity of the adjacent crystals. In the present study, we experimentally observed a Σ9 grain-boundary atomic structure of a bcc crystal (Fe-3%Si). It is found that the Σ9 grain-boundary structure is largely reconstructed and forms a dense packing of icosahedral clusters in its core. Combining with the detailed theoretical calculations, the Σ9 grain-boundary atomic structure is discovered to be incommensurate with the adjacent crystal structures. The present findings shed new light on the study of stable grain-boundary atomic structures in crystalline materials.

SUBMITTER: Seki T

PROVIDER: S-EPMC10697943 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature

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Incommensurate grain-boundary atomic structure.

Seki Takehito T Futazuka Toshihiro T Morishige Nobusato N Matsubara Ryo R Ikuhara Yuichi Y Shibata Naoya N

Nature communications 20231205 1

Grain-boundary atomic structures of crystalline materials have long been believed to be commensurate with the crystal periodicity of the adjacent crystals. In the present study, we experimentally observed a Σ9 grain-boundary atomic structure of a bcc crystal (Fe-3%Si). It is found that the Σ9 grain-boundary structure is largely reconstructed and forms a dense packing of icosahedral clusters in its core. Combining with the detailed theoretical calculations, the Σ9 grain-boundary atomic structure ...[more]

PMID: 38052780

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