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Mechanisms for <100> interstitial dislocation loops to diffuse in BCC iron.

ABSTRACT: The mobility of dislocation loops in materials is a principle factor in understanding the mechanical strength, and the evolution of microstructures due to deformation and radiation. In body-centered cubic (BCC) iron, the common belief is that <100> interstitial dislocation loops are immobile once formed. However, using self-adaptive accelerated molecular dynamics (SSAMD), a new diffusion mechanism has been discovered for <100> interstitial dislocation loops. The key aspect of the mechanism is the changing of the habit planes between the {100} plane and the {110} plane, which provides a path for the <100> loops to diffuse one-dimensionally. The migration behavior modeled with SSAMD is further confirmed by in-situ transmission electron microscopy (TEM) measurements, and represents a significant step for understanding the formation of <100> loop walls and the mechanical behavior of BCC Fe under irradiation.

SUBMITTER: Gao N

PROVIDER: S-EPMC7801622 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Mechanisms for <100> interstitial dislocation loops to diffuse in BCC iron.

Gao N N Yao Z W ZW Lu G H GH Deng H Q HQ Gao F F

Nature communications 20210111 1

The mobility of dislocation loops in materials is a principle factor in understanding the mechanical strength, and the evolution of microstructures due to deformation and radiation. In body-centered cubic (BCC) iron, the common belief is that <100> interstitial dislocation loops are immobile once formed. However, using self-adaptive accelerated molecular dynamics (SSAMD), a new diffusion mechanism has been discovered for <100> interstitial dislocation loops. The key aspect of the mechanism is th ...[more]

PMID: 33431875

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