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First-principles calculations on dislocations in MgO.

ABSTRACT: While ceramic materials are widely used in our society, their understanding of the plasticity is not fully understood. MgO is one of the prototypical ceramics, extensively investigated experimentally and theoretically. However, there is still controversy over whether edge or screw dislocations glide more easily. In this study, we directly model the atomic structures of the dislocation cores in MgO based on the first-principles calculations and estimate the Peierls stresses. Our results reveal that the screw dislocation on the primary slip system exhibits a smaller Peierls stress than the edge dislocation. The tendency is not consistent with metals, but rather with TiN, suggesting a characteristic inherent to rock-salt type materials.

SUBMITTER: Kiyohara S

PROVIDER: S-EPMC11370692 | biostudies-literature | 2024

REPOSITORIES: biostudies-literature

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First-principles calculations on dislocations in MgO.

Kiyohara Shin S Tsuru Tomohito T Kumagai Yu Y

Science and technology of advanced materials 20240819 1

While ceramic materials are widely used in our society, their understanding of the plasticity is not fully understood. MgO is one of the prototypical ceramics, extensively investigated experimentally and theoretically. However, there is still controversy over whether edge or screw dislocations glide more easily. In this study, we directly model the atomic structures of the dislocation cores in MgO based on the first-principles calculations and estimate the Peierls stresses. Our results reveal th ...[more]

PMID: 39229345

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