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Role of dislocation elastic field on impurity segregation in Fe-based alloys.

ABSTRACT: Dislocation engineering in crystalline materials is essential when designing materials for a large range of applications. Segregation of additional elements at dislocations is frequently used to modify the influence of dislocations on material properties. Thus, the influence of the dislocation elastic field on impurity segregation is of major interest, as its understanding should lead to engineering solutions that improve the material properties. We report the experimental study of the elastic field influence on atomic segregation in the core and in the area surrounding edge dislocations in Fe-based alloys. Each element is found either to segregate in the edge dislocation core or to form atmospheres. The elastic field has a strong effect on the segregation atmosphere, but no effect on the dislocation core segregation. The theory is in good agreement with experiments, and should support dislocation engineering.

SUBMITTER: Medouni I

PROVIDER: S-EPMC7815746 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Role of dislocation elastic field on impurity segregation in Fe-based alloys.

Medouni I I Portavoce A A Maugis P P Eyméoud P P Yescas M M Hoummada K K

Scientific reports 20210119 1

Dislocation engineering in crystalline materials is essential when designing materials for a large range of applications. Segregation of additional elements at dislocations is frequently used to modify the influence of dislocations on material properties. Thus, the influence of the dislocation elastic field on impurity segregation is of major interest, as its understanding should lead to engineering solutions that improve the material properties. We report the experimental study of the elastic f ...[more]

PMID: 33469073

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