Journal article
Deformation in nanocrystalline ceramics: A microstructural study of MgAl2O4
Acta materialia, v 183
15 Jan 2020
Abstract
Contrary to the characteristic strengthening of polycrystalline ceramics with a decrease in grain size, extremely fine nanocrystalline ceramics exhibit softening, increased plasticity and an inverse Hall-Petch relation. Despite experimental evidence, questions remain regarding the underlying deformation mechanisms governing this abnormal mechanical behavior. In the present study, an in-depth microstructural examination was performed on nanostructured transparent magnesium aluminate spinel (MgAl2O4) subjected to microhardness tests. Microstructural observations revealed regions strained to various degrees below the point of indentation, containing varying amounts of dislocations and nano-cavities. Furthermore, the residual strain in different areas was estimated by local electron diffraction. These observations and analysis provided evidence for grain boundary (GB) mediated mechanisms (e.g., GB sliding and rotation). Moreover, shear bands formed and were found to be associated with micro-cracking. By combining the microstructural analysis with suitable models, it was concluded that these mechanisms govern plastic deformation. By elucidating how strain is accommodated within nanocrystalline ceramics, a deeper understanding of their unique mechanical behavior is gained.
[Display omitted]
Metrics
Details
- Title
- Deformation in nanocrystalline ceramics: A microstructural study of MgAl2O4
- Creators
- Barak Ratzker - Ben-Gurion University of the NegevAvital Wagner - Ben-Gurion University of the NegevMaxim Sokol - Drexel UniversityLouisa Meshi - Ben-Gurion University of the NegevSergey Kalabukhov - Ben-Gurion University of the NegevNachum Frage - Ben-Gurion University of the Negev
- Publication Details
- Acta materialia, v 183
- Publisher
- Elsevier
- Resource Type
- Journal article
- Language
- English
- Academic Unit
- Materials Science and Engineering
- Web of Science ID
- WOS:000506465100011
- Scopus ID
- 2-s2.0-85074955728
- Other Identifier
- 991019168361904721
InCites Highlights
Data related to this publication, from InCites Benchmarking & Analytics tool:
- Collaboration types
- Domestic collaboration
- International collaboration
- Web of Science research areas
- Materials Science, Multidisciplinary
- Metallurgy & Metallurgical Engineering