Mechanically driven grain boundary relaxation: a mechanism for cyclic hardening in nanocrystalline Ni

TitleMechanically driven grain boundary relaxation: a mechanism for cyclic hardening in nanocrystalline Ni
Publication TypeJournal Article
Year of Publication2012
AuthorsRupert, TJ, Schuh, CA
JournalPhilosophical Magazine Letters
Volume92
Issue1
Pagination20 - 28
Date Published2012///
Abstract

Molecular dynamics simulations are used to show that cyclic mechanical loading can relax the non-equilibrium grain boundary (GB) structures of nanocrystalline metals by dissipating energy and reducing the average atomic energy of the system, leading to higher strengths. The GB processes that dominate deformation in these materials allow low-energy boundary configurations to be found through kinematically irreversible structural changes during cycling, which increases the subsequent resistance to plastic deformation.