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Decoupling between Shockley partials and stacking faults strengthens multiprincipal element alloys.

ABSTRACT: Mechanical properties are fundamental to structural materials, where dislocations play a decisive role in describing their mechanical behavior. Although the high-yield stresses of multiprincipal element alloys (MPEAs) have received extensive attention in the last decade, the relation between their mechanistic origins remains elusive. Our multiscale study of density functional theory, atomistic simulations, and high-resolution microscopy shows that the excellent mechanical properties of MPEAs have diverse origins. The strengthening effects through Shockley partials and stacking faults can be decoupled in MPEAs, breaking the conventional wisdom that low stacking fault energies are coupled with wide partial dislocations. This study clarifies the mechanistic origins for the strengthening effects, laying the foundation for physics-informed predictive models for materials design.

SUBMITTER: Pei Z

PROVIDER: S-EPMC8713770 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Decoupling between Shockley partials and stacking faults strengthens multiprincipal element alloys.

Pei Zongrui Z Zhang Siyuan S Lei Yinkai Y Zhang Fan F Chen Mingwei M

Proceedings of the National Academy of Sciences of the United States of America 20211201 51

Mechanical properties are fundamental to structural materials, where dislocations play a decisive role in describing their mechanical behavior. Although the high-yield stresses of multiprincipal element alloys (MPEAs) have received extensive attention in the last decade, the relation between their mechanistic origins remains elusive. Our multiscale study of density functional theory, atomistic simulations, and high-resolution microscopy shows that the excellent mechanical properties of MPEAs hav ...[more]

PMID: 34916294

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