Journal article
Direct observation of a coincident dislocation- and grain boundary-mediated deformation in nanocrystalline iron
Materials science & engineering. A, Structural materials : properties, microstructure and processing, v 709(C), pp 339-348
02 Jan 2018
Abstract
The vast majority of our understanding about the deformation Mechanisms in nanocrystalline materials is limited to information gained from experimental and theoretical characterization of FCC materials. Related behavior in nanocrystalline BCC materials is not as frequently studied, and thus outstanding questions remain regarding deformation regimes and Hall-Petch trends. Using in situ TEM, we investigate the deformation mechanisms of nanocrystalline BCC iron films with an average grain size of 35 nm produced by physical vapor deposition. The tensile experiments showed that fracture resulted after strains of about 5%. Crack propagation occurred primarily by separation of grain boundaries at the crack tip, which was accompanied by localized intragranular ductile (often superplastic) fracture. Deformation at the crack tip was accommodated by dislocation motion, grain rotation, and grain growth. No evidence was observed of twinning in nanocrystalline BCC iron. The concurrent nature of the grain rotation and dislocation motion indicates that grain rotation occurs at fairly large grain sizes and there is no sharp transition from dislocation-mediated to grain boundary sliding mechanisms as grain size is decreased in BCC iron.
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Details
- Title
- Direct observation of a coincident dislocation- and grain boundary-mediated deformation in nanocrystalline iron
- Creators
- G. Vetterick - Drexel UniversityA. C. Leff - Drexel UniversityM. Marshall - Sandia National LaboratoriesJ. K. Baldwin - Los Alamos National LaboratoryA. Misra - Los Alamos National LaboratoryK. Hattar - Sandia National LaboratoriesM. L. Taheri - Drexel University
- Publication Details
- Materials science & engineering. A, Structural materials : properties, microstructure and processing, v 709(C), pp 339-348
- Publisher
- Elsevier
- Number of pages
- 10
- Grant note
- DEAC52-06NA25396 / U.S. Department of Energy (DOE) Office of Science by Los Alamos National Laboratory DE-SC0008274 / United States Department of Energy Basic Energy Sciences (DOE/BES) under the Early Career program; United States Department of Energy (DOE) DEAC04-94AL85000 / Sandia National Laboratories; United States Department of Energy (DOE) DE-NA-0003525 / U.S. Department of Energy's National Nuclear Security Administration; National Nuclear Security Administration
- Resource Type
- Journal article
- Language
- English
- Academic Unit
- Pediatrics
- Web of Science ID
- WOS:000416879200039
- Scopus ID
- 2-s2.0-85031328013
- Other Identifier
- 991019167922904721
InCites Highlights
Data related to this publication, from InCites Benchmarking & Analytics tool:
- Collaboration types
- Domestic collaboration
- Web of Science research areas
- Materials Science, Multidisciplinary
- Metallurgy & Metallurgical Engineering
- Nanoscience & Nanotechnology