Effects of grain boundary disorder on dislocation emission

Journal Article · Tue Nov 20 00:00:00 EST 2018 · Materials Letters

DOI:https://doi.org/10.1016/j.matlet.2018.11.114· OSTI ID:1492058

Borovikov, Valery ^[1]; Mendelev, Mikhail I. ^[1]; King, Alexander H. ^[2]

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1. Ames Lab., Ames, IA (United States). Division of Materials Sciences and Engineering
2. Ames Lab., Ames, IA (United States). Division of Materials Sciences and Engineering; Iowa State Univ., Ames, IA (United States). Dept. of Materials Science and Engineering

It was recently reported that segregation of Zr to grain boundaries (GB) in nanocrystalline Cu can lead to the development of disorder in the intergranular structure (Khalajhedayati et al., 2016; Khalajhedayati and Rupert, 2015). In this study we employ atomistic computer simulations to investigate how this disorder affects dislocation nucleation from the GBs under applied stress. It was found that a fully disordered grain boundary structure suppresses dislocation emission and significantly increases the yield stress. Depending on the solute concentration and heat-treatment, however, partial disorder may also occur and this aids dislocation nucleation rather than suppressing it, reducing or eliminating the strengthening effect.

• Research Organization: Ames Laboratory (AMES), Ames, IA (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: AC02-07CH11358
• OSTI ID: 1492058
• Alternate ID(s): OSTI ID: 1636183
• Report Number(s): IS-J--9843; PII: S0167577X18318810
• Journal Information: Materials Letters, Journal Name: Materials Letters Journal Issue: C Vol. 237; ISSN 0167-577X
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Deformation and fracture
Dislocation nucleation
Grain boundaries
Molecular dynamics simulation
Monte Carlo simulation
Yield stress