Nanoscale ductility in <i>c</i> ‐plane Al <sub>2</sub> O <sub>3</sub> : Dislocation and twinning mechanisms via nanoindentation and molecular dynamics
Abstract Brittle oxides, such as α‐Al 2 O 3 , i.e., sapphire, are traditionally unsuitable for ductile applications, yet exhibit enhanced plasticity at nanoscale. This study explores the mechanical behavior of c ‐plane‐oriented, dislocation‐free monocrystalline α‐Al 2 O 3 via molecular dynamics (MD) simulations and experiments, including nanoindentation and post‐indentation TEM analysis. The results demonstrate high strength with homogeneous, extensive deformation without failure. Plasticity is dominated by basal (0001) dislocations and rhombohedral [102] twins, which nucleate at deformation onset, as confirmed by MD and TEM. Generalized stacking fault energy (GSFE) and twinning fault energy (TFE) calculations elucidate mechanisms that mitigate crack initiation and propagation on the c ‐plane, aligning simulations with observations. These insights advance the understanding of nanoscale ductility in oxides, broadening the utility of sapphire in load‐bearing micro/nano devices.
Authors
- K. Mulewska (ORCID: https://orcid.org/0000-0001-6863-9431)
- Witold Chromiński (ORCID: https://orcid.org/0000-0002-5345-7667)
- Fabrizio Rovaris (ORCID: https://orcid.org/0000-0002-0729-5409)
- Ł. Kurpaska (ORCID: https://orcid.org/0000-0002-2970-4090)
- Ibrahim Goda (ORCID: https://orcid.org/0000-0001-5508-0261)
- Damian Kalita (ORCID: https://orcid.org/0000-0003-1135-6873)
- A. Zaborowska
- Wenyi Huo (ORCID: https://orcid.org/0000-0001-8297-9045)
- Claudio Fusco (ORCID: https://orcid.org/0000-0001-8409-5681)
- Qinqin Xu (ORCID: https://orcid.org/0000-0003-1624-9380)
Institutions
- Université Claude Bernard Lyon 1 (FR)
- Warsaw University of Technology (PL)
- Centre National de la Recherche Scientifique (FR)
- Nanjing Forestry University (CN)
- Arts et Métiers (FR)
- National Centre for Nuclear Research (PL)
- Matériaux Ingénierie et Science (FR)
- Laboratoire d'Étude des Microstructures et de Mécanique des Matériaux (FR)
- HESAM Université (FR)
- Institut National des Sciences Appliquées de Lyon (FR)
- University of Milano-Bicocca (IT)
Publication Details
- Journal
- Journal of the American Ceramic Society
- Published
- 2025-12-05
- DOI
- https://doi.org/10.1111/jace.70420
- Citations
- 1
- Primary Topic
- Microstructure and mechanical properties
- Type
- article
- Field-Weighted Citation Impact
- 0.52
Funders
- European Commission
- Fundacja na rzecz Nauki Polskiej
- European Regional Development Fund