Grain boundaries are Brownian ratchets
We demonstrate that grain boundaries (GBs) behave as Brownian ratchets, exhibiting direction-dependent mobilities and unidirectional motion under oscillatory driving forces or cyclic thermal annealing. We observed these phenomena for nearly all nonsymmetric GBs but not for symmetric ones. Our observations build on molecular dynamics and phase-field crystal simulations for a wide range of GB types and driving forces in both bicrystal and polycrystalline microstructures. We corroborate these simulation results through in situ experimental observations. We analyze these results with a Markov chain model and explore the implications of GB ratchet behavior for materials processing and microstructure tailoring.
Authors
- Xiaoqing Pan (ORCID: https://orcid.org/0000-0002-0965-8568)
- Jian Han (ORCID: https://orcid.org/0000-0002-3800-9436)
- Caihao Qiu (ORCID: https://orcid.org/0000-0001-9927-3938)
- Maik Punke (ORCID: https://orcid.org/0000-0002-3564-7942)
- David J. Srolovitz (ORCID: https://orcid.org/0000-0001-6038-020X)
- Marco Salvalaglio (ORCID: https://orcid.org/0000-0002-4217-0951)
- Yishi Su (ORCID: https://orcid.org/0000-0001-7571-6992)
- Siqi Wang (ORCID: https://orcid.org/0000-0002-7182-394X)
- Yuan Tian (ORCID: https://orcid.org/0000-0002-7074-5468)
- Ying Han (ORCID: https://orcid.org/0000-0002-6621-2351)
Institutions
- City University of Hong Kong (HK)
- Shanghai Jiao Tong University (CN)
- University of California, Irvine (US)
- Technische Universität Dresden (DE)
- University of Hong Kong (HK)
Publication Details
- Journal
- Science
- Published
- 2024-08-29
- DOI
- https://doi.org/10.1126/science.adp1516
- Citations
- 26
- Primary Topic
- Solidification and crystal growth phenomena
- Type
- article
- Field-Weighted Citation Impact
- 3.05