Presentation Information
[P2-47]Investigation of Multiscale Structural and Compositional Optimization on Magnetic Properties in ThMn12-type Permanent Magnets
*Hui-Dong Qian1, Jingzhi Han1, Tao Zhu1, Qiang Gao1, Jinbo Yang1,2,3,4 (1. Institute of Condensed Matter and Material Physics, School of Physics, Peking University (China), 2. State Key Laboratory for Mesoscopic Physics and School of Physics, Peking University (China), 3. Beijing Key Laboratory for Magnetoelectric Materials and Devices (China), 4. Peking University Yangtze Delta Institute of Optoelectronics (China))
Keywords:
SmFe12-based magnet
Rare-earth intermetallic compounds R(Fe,M)12 (R = rare earth elements, M = transition metals) with ThMn12-type structure have been recognized as promising permanent magnetic materials since the 1980s [1]. Recent studies indicate that certain Sm-based ThMn12-type compounds exhibit superior intrinsic magnetic properties compared to Nd2Fe14B, yet their extrinsic magnetic performance remains insufficient for practical applications [2-4]. Conventional approaches face inherent contradictions when attempting to simultaneously enhance coercivity and magnetization.
This study overcomes these limitations through multiscale optimization strategies. For compositional design: 1) Zr and B elements were employed to optimize fundamental magnetic properties and phase stability, establishing stable main phase structures; 2) Ce and Si elements were introduced to regulate crystallinity and optimize material costs. Structurally, a gradient grain architecture was constructed via melt-spinning process to achieve collaborative multiscale grain effects.
Microstructural characterization confirmed that compositional optimization effectively reduced the content of non-magnetic stabilizing elements in the main phase, while the gradient structure inhibited magnetization reversal through grain boundary regulation. The optimized magnets demonstrated breakthrough performance: Ms≈141 emu/g, Mr≈93 emu/g, Hc≈9500 Oe, and (BH)max≈16 MGOe. The research proves that the synergetic effects of compositional regulation and gradient structure design enable simultaneous enhancement of high coercivity and magnetization while reducing non-magnetic element content.
References
[1] Y.C. Yang, B. Kebe, J. James, W. Yelon, J. Appl. Phys. 1981, 52: 2077.
[2] Y. Hirayama, Y.K. Takahashi, S. Hirosawa, and K. Hono, Scripta Mater. 2017, 138: 62-65.
[3] J.S. Zhang, X. Tang, H. Sepehri-Amin, A.K. Srinithi, T. Ohkubo, and K. Hono, Acta Mater. 2021, 217: 117161.
[4] A.K. Srinithi, H. Sepehri-Amin, Xin Tang, P. Tozman, J. Li, J. Zhang, S. Kobayashi, T. Ohkubo, T. Nakamura, and K. Hono, J. Magn. Magn. Mater. 2021, 529: 167866.
This study overcomes these limitations through multiscale optimization strategies. For compositional design: 1) Zr and B elements were employed to optimize fundamental magnetic properties and phase stability, establishing stable main phase structures; 2) Ce and Si elements were introduced to regulate crystallinity and optimize material costs. Structurally, a gradient grain architecture was constructed via melt-spinning process to achieve collaborative multiscale grain effects.
Microstructural characterization confirmed that compositional optimization effectively reduced the content of non-magnetic stabilizing elements in the main phase, while the gradient structure inhibited magnetization reversal through grain boundary regulation. The optimized magnets demonstrated breakthrough performance: Ms≈141 emu/g, Mr≈93 emu/g, Hc≈9500 Oe, and (BH)max≈16 MGOe. The research proves that the synergetic effects of compositional regulation and gradient structure design enable simultaneous enhancement of high coercivity and magnetization while reducing non-magnetic element content.
References
[1] Y.C. Yang, B. Kebe, J. James, W. Yelon, J. Appl. Phys. 1981, 52: 2077.
[2] Y. Hirayama, Y.K. Takahashi, S. Hirosawa, and K. Hono, Scripta Mater. 2017, 138: 62-65.
[3] J.S. Zhang, X. Tang, H. Sepehri-Amin, A.K. Srinithi, T. Ohkubo, and K. Hono, Acta Mater. 2021, 217: 117161.
[4] A.K. Srinithi, H. Sepehri-Amin, Xin Tang, P. Tozman, J. Li, J. Zhang, S. Kobayashi, T. Ohkubo, T. Nakamura, and K. Hono, J. Magn. Magn. Mater. 2021, 529: 167866.