Segregation-affected yielding and stability in nanotwinned silver by microalloying
- Univ. of Vermont, Burlington, VT (United States). Materials Science Program
- Univ. of Vermont, Burlington, VT (United States). Materials Science Program; Univ. of Vermont, Burlington, VT (United States). Dept. of Mechanical Engineering
Small-scale mechanics of solute atom segregation and incipient plasticity in nanotwinned Ag containing trace concentrations of Cu were studied by using large-scale hybrid Monte-Carlo and molecular-dynamic simulations. It is found that solute Cu atoms are segregated concurrently to grain boundaries and intrinsic twin-boundary kink-step defects during thermal annealing. Low Cu dopant contents below 1 at. % are predicted to substantially increase twin stability in nanotwinned Ag, accompanied with a pronounced rise in yield strength at 300 K. Incipient plasticity is associated with kink-step migration, grain-boundary sliding, and dislocation nucleation from grain boundaries and twin-boundary defects, which are affected by doping. Cu-dependent yield strengthening in doped nanotwinned Ag is shown to correlate with the critical stress required to initiate crystal slip emitted from grain boundaries and twin-boundary defects. Finally, these findings provide fundamental insight into the roles of twin-boundary imperfections on plastic yielding, and offer new clues to further extend the extraordinary stability and strength of nanotwinned metals by microalloying.
- Research Organization:
- Univ. of Vermont, Burlington, VT (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF)
- Grant/Contract Number:
- SC0016270; DMR-1410646; ACI-1548562
- OSTI ID:
- 1410783
- Alternate ID(s):
- OSTI ID: 1410729
- Journal Information:
- Physical Review Materials, Vol. 1, Issue 6; Related Information: http://link.aps.org/supplemental/10.1103/PhysRevMaterials.1.063604; ISSN 2475-9953
- Publisher:
- American Physical Society (APS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Atomistic modeling of interfacial segregation and structural transitions in ternary alloys
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journal | November 2018 |
Ideal maximum strengths and defect-induced softening in nanocrystalline-nanotwinned metals
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journal | September 2019 |
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