Identifying grain boundary and intragranular pinning centres in Sm2(Co,Fe,Cu,Zr)17 permanent magnets to guide performance optimisation
Permanent magnets draw their properties from a complex interplay of chemical composition and phase, each with their associated intrinsic magnetic properties. Gaining an understanding of these interactions is the key to deciphering the origins of a permanent magnets' magnetic performance and facilitate the engineering of much improved-performing magnets. Here, we use advanced multiscale microscopy and microanalysis on a bulk Sm<sub>2</sub>(Co,Fe,Cu,Zr)<sub>17</sub> pinning-type high-performance magnet with outstanding thermal and chemical stability. Comparison of the microstructure in regions of different composition, we demonstrate that the pinning of magnetic domains, imaged by nanoscale magnetic induction mapping, is controlled by the composition and atomic arrangement of copper. This is confirmed by micromagnetic simulations. Contrary to the belief that grain boundaries are "weak links" in magnetic materials, we demonstrate grain boundaries undergo magnetization reversal at relatively low fields (0.1-0.3 T), but this remains confined to these regions and does not significantly impact the magnet's coercivity. Our results showcase that it is the optimal microstructure within the grain itself that is crucial for achieving the desired magnetic properties.
Authors
- Konstantin Skokov (ORCID: https://orcid.org/0000-0003-4321-9021)
- Oliver Gutfleisch (ORCID: https://orcid.org/0000-0001-8021-3839)
- Kaan Üstüner
- Leopoldo Molina‐Luna (ORCID: https://orcid.org/0000-0002-9412-8093)
- Iliya Radulov (ORCID: https://orcid.org/0000-0001-8943-5083)
- Nikita Polin (ORCID: https://orcid.org/0009-0001-2382-2408)
- Stefan Giron
- Fernando Maccari (ORCID: https://orcid.org/0000-0002-4585-4179)
- Karsten Durst (ORCID: https://orcid.org/0000-0002-9246-6398)
- Michael Farle (ORCID: https://orcid.org/0000-0002-1864-3261)
- Yangyiwei Yang (ORCID: https://orcid.org/0000-0001-5505-7117)
- Esmaeil Adabifiroozjaei (ORCID: https://orcid.org/0000-0002-5095-2419)
- M. Katter
- Dominik Ohmer (ORCID: https://orcid.org/0000-0002-7129-331X)
- Bai‐Xiang Xu (ORCID: https://orcid.org/0000-0001-5906-5341)
- Lambert Alff (ORCID: https://orcid.org/0000-0001-8185-4275)
- András Kovács (ORCID: https://orcid.org/0000-0001-8485-991X)
- Katharina Ollefs (ORCID: https://orcid.org/0000-0002-2301-4670)
- Christoph Freysoldt (ORCID: https://orcid.org/0000-0002-7896-3478)
- Rafal E. Dunin–Borkowski (ORCID: https://orcid.org/0000-0001-8082-0647)
- Alaukik Saxena
- Trevor P. Almeida (ORCID: https://orcid.org/0000-0003-4683-6279)
- Baptiste Gault (ORCID: https://orcid.org/0000-0002-4934-0458)
- Hongbin Zhang (ORCID: https://orcid.org/0000-0002-1035-8861)
Institutions
- Centre National de la Recherche Scientifique (FR)
- Royal Veterinary College (GB)
- Forschungszentrum Jülich (DE)
- Ernst Ruska Centre (DE)
- Technische Universität Darmstadt (DE)
- Max-Planck-Institut für Nachhaltige Materialien (DE)
- Vacuumschmelze (Germany) (DE)
- Groupe de Physique des Matériaux (FR)
- Imperial College London (GB)
- University of Duisburg-Essen (DE)
- Université de Rouen Normandie (FR)
- University of Glasgow (GB)
- Institut National des Sciences Appliquées Rouen Normandie (FR)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-12-20
- DOI
- https://doi.org/10.1038/s41467-025-67773-7
- Citations
- 1
- Primary Topic
- Magnetic Properties of Alloys
- Type
- article
- Field-Weighted Citation Impact
- 0.43
Funders
- Deutsche Forschungsgemeinschaft
- Bundesministerium für Bildung und Forschung
- International Max Planck Research School for Advanced Methods in Process and Systems Engineering
- Leibniz-Gemeinschaft