Additive manufacturing of Nd-Fe-B permanent magnets and their application in electrical machines

Wu, Julan; Korman, Oguz; Di Nardo, Mauro; Degano, Michele; Gerada, Chris; Ashcroft, Ian; J.M. Hague, Richard; T. Aboulkhair, Nesma

Abstract

Powder Bed Fusion - Laser Beam (PBF-LB), a form of additive manufacturing (AM) for Nd-Fe-B permanent magnets, is attracting substantial interest for its ability to process functional magnetic materials while capitalizing on AM's design flexibility and waste reduction. As the demand for rare-earth magnets declines due to scarcity and high costs, AM emerges as a pivotal player in the future of electrical machines. However, crack formation and delamination during laser-based AM hinder the production of hard magnetic Nd-Fe-B components, compromising part integrity. This paper addresses these challenges by successfully controlling laser scan strategies and presenting an approach to minimize delamination. Resin infiltration is explored as a potential solution to mitigate residual cracking. Optimized scan strategies and resin infiltration enhance the structural integrity of printed magnets, meeting specific application requirements. As a vessel to investigate the proposed approach for the AM of Nd-Fe-B magnets, a Permanent Magnet assisted Synchronous Reluctance motor has been designed using a particular shape of permanent magnets enabled by the AM. Experimental results align with the FE findings, showcasing a 12% increase in average torque using PBF-LB-produced permanent magnets. This indicates that AM's enhanced design freedom, unconventional shapes, and minimal post-processing contribute to improved reliability, efficiency, and overall performance.

Citation

Wu, J., Korman, O., Di Nardo, M., Degano, M., Gerada, C., Ashcroft, I., J.M. Hague, R., & T. Aboulkhair, N. (2024). Additive manufacturing of Nd-Fe-B permanent magnets and their application in electrical machines. IEEE Access, 12, 138921-138931. https://doi.org/10.1109/ACCESS.2024.3436643

• Journal Article Type: Article
• Acceptance Date: Aug 1, 2024
• Online Publication Date: Aug 1, 2024
• Publication Date: Jan 1, 2024
• Deposit Date: Sep 16, 2024
• Publicly Available Date: Sep 18, 2024
• Journal: IEEE Access
• Electronic ISSN: 2169-3536
• Publisher: Institute of Electrical and Electronics Engineers
• Peer Reviewed: Peer Reviewed
• Volume: 12
• Pages: 138921-138931
• DOI: https://doi.org/10.1109/ACCESS.2024.3436643
• Public URL: https://nottingham-repository.worktribe.com/output/37947538
• Publisher URL: https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10620235