Dislocations interaction induced structural instability in intermetallic Al₂Cu

Authors

Qing Zhou, Xi’an Jiaotong University
Jian Wang, University of Nebraska-LincolnFollow
Amit Misra, University of Michigan - Ann Arbor
Ping Huang, Xi’an Jiaotong UniversityFollow
Fei Wang, Xi’an Jiaotong UniversityFollow
Kewei Xu, Xi’an Jiaotong University

Document Type

Article

Date of this Version

2017

Citation

npj Computational Materials (2017) 3:24 ; doi:10.1038/s41524-017-0030-2.

Comments

© The Author(s) 2017. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License.

Abstract

Intermetallic precipitates are widely used to tailor mechanical properties of structural alloys but are often destabilized during plastic deformation. Using atomistic simulations, we elucidate structural instability mechanisms of intermetallic precipitates associated with dislocation motion in a model system of Al₂Cu. Interaction of non-coplanar <001> dislocation dipoles during plastic deformation results in anomalous reactions—the creation of vacancies accompanied with climb and collective glide of <001> dislocation associated with the dislocation core change and atomic shuffle—accounting for structural instability in intermetallic Al₂Cu. This process is profound with decreasing separation of non-coplanar dislocations and increasing temperature and is likely to be operative in other non-cubic intermetallic compounds as well.