Alloying induces directionally-dependent mobility and alters migration mechanisms of faceted grain boundaries

SCRIPTA MATERIALIA

卷:194

Article

McCarthy, Megan J.¹  Rupert, Timothy J.^1,2 

[1] Univ Calif Irvine, Mat & Mfg Technol, Irvine, CA 92697 USA

[2] Univ Calif Irvine, Dept Mat Sci & Engn, Irvine, CA 92697 USA

关键词: Grain boundary migration;    Grain boundary defects;    Grain boundary segregation;    Defect mobility;   

DOI  :  10.1016/j.scriptamat.2020.113643

来源: Elsevier

【 摘 要 】

Faceted grain boundaries exhibit unusual segregation and migration tendencies. To gain a deeper understanding of how solute atoms interact with faceted interfacial structures during migration, this study probes the migration behavior of a faceted Sigma 11 boundary in Cu doped with Ag atoms. The solutes are found to segregate to the facet with more free volume and strongly reduce boundary velocity in one migration direction, but not the other, due to the presence of a directionally-dependent motion mechanism that can escape solute pinning and therefore speed up migration. Hence, a new mechanism of chemically-induced anisotropy in grain boundary mobility is uncovered by these simulations. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

Free