Journal of the Korean Society for Heat Treatment (열처리공학회지)

The Korean Society for Heat Treatment (한국열처리공학회)
권호 표지
DOI QR코드

DOI QR Code

Influence of Post-Sintering Annealing Conditions on the Microstructure and Magnetic Properties of Nd-Fe-B Magnet

Nd-Fe-B 소결자석의 소결 후 열처리 조건에 따른 미세조직 및 자기적 특성 변화

  • Yunjong Jung (Division of Advanced Materials Engineering, Kongju National University) ;
  • Soonjik Hong (Division of Advanced Materials Engineering, Kongju National University) ;
  • Dong-Hwan Kim (R&D Center of Star Group Ind. Co., Ltd.) ;
  • Kyoung-Hoon Bae (R&D Center of Star Group Ind. Co., Ltd.) ;
  • Gian Song (Division of Advanced Materials Engineering, Kongju National University)
  • 정윤종 (공주대학교 신소재공학과) ;
  • 홍순직 (공주대학교 신소재공학과) ;
  • 김동환 ((주)성림첨단산업 R&D 센터) ;
  • 배경훈 ((주)성림첨단산업 R&D 센터) ;
  • 송기안 (공주대학교 신소재공학과)
  • Received : 2023.12.12
  • Accepted : 2024.01.24
  • Published : 2024.01.30
Download PDF
⟨ Previous Next ⟩

Abstract

Nd-Fe-B permanent magnets have been utilized on various industrial fields such as electric vehicles, generator, robots with actuator, etc, due to their outstanding magnetic properties even 10 times better than conventional magnets. Recently, there are many researches that report magnetic properties improved by controlling microstructure through adjusting alloying elements or conducting various processing. Especially, post-sintering annealing (PSA) can significantly improve the coercivity by modifying the distribution and morphology of Nd-rich phase which formed at grain boundaries. In this study, Nd-Fe-B sintered magnets were subjected to primary heat treatment followed by secondary heat treatment at 460℃, 500℃, and 540℃ to investigate the changes in microstructure and magnetic properties with the secondary heat treatment temperature. EBSD analysis was conducted to compare anisotropic characteristics. Through the SEM and TEM observation for analyzing the morphology and distribution of Nd-rich phase, we investigated the relationship between microstructure and magnetic properties of sintered Nd-Fe-B magnets.

Keywords

Acknowledgement

본 논문은 산업통상자원부의 재원으로 한국산업기술평가관리원의 지원을 받아 수행한 연구임(20010817). 본 논문은 산업통상자원부 및 한국산업기술진흥원의 기반구축 사업의 지원을 받아 수행된 연구임(No. P0018009). 본 논문은 교육부의 재원으로 한국연구재단의 지원을 받아 수행된 지자체-대학 협력기반 지역혁신 사업의 지원을 받아 수행된 연구임(No. 2021RIS-004).

References

  1. Y. Matsuura: J. Magn. Magn. Mater. 303(2) (2006) 344-347.  https://doi.org/10.1016/j.jmmm.2006.01.171
  2. S. Hirosawa, K. Tokuhara, Y. Matsuura, H. Yamamoto, S. Fujimura, and M. Sagawa: J. Magn. Magn. Mater. 61(3) (1986) 363-369.  https://doi.org/10.1016/0304-8853(86)90050-8
  3. R. Lai, R. Chen, W. Yin, X. Tang, Z. Wang, C. Jin, D. Lee, and A. Yan: J. Alloys Compd. 724 (2017) 275-279.  https://doi.org/10.1016/j.jallcom.2017.06.290
  4. G. Bai, R. Gao, Y. Sun, G. Han, and B. Wang: J. Magn. Magn. Mater. 308(1) (2007) 20-23.  https://doi.org/10.1016/j.jmmm.2006.04.029
  5. M. Sagawa, S. Fujimura, N. Togawa, H. Yamamoto, and Y. Matsuura: J. Appl. Phys. 55(6) (1984) 2083-2087.  https://doi.org/10.1063/1.333572
  6. X.D. Xu, T. T. Sasaki, J. N. Li, Z. J. Dong, H. Sepehri-Amin, T. H. Kim, T. Ohkubo, T. Schrefl, and K. Hono: Acta Mater. 156 (2018) 146-157.  https://doi.org/10.1016/j.actamat.2018.06.037
  7. B. Davies, R. Mottram, and I. Harris: Mater. Chem. Phys. 67(1-3) (2001) 272-281.  https://doi.org/10.1016/S0254-0584(00)00450-8
  8. W. F. Li, T. Ohkubo, T. Akiya, H. Kato, and K. Hono: J. Mater. Res. 24(2) (2009) 413-420.  https://doi.org/10.1557/JMR.2009.0041
  9. T.-H. Kim, S.-R. Lee, K.-H. Bae, H.-J. Kim, M.-W. Lee, and T.-S. Jang: Acta Mater. 133 (2017) 200-207.  https://doi.org/10.1016/j.actamat.2017.05.046
  10. Y. L. Liu, J. Liang, Y. C. He, Y. F. Li, G. F. Wang, Q. Ma, F. Liu, Y. Zhang, and X. F. Zhang: AIP Advances 8(5) (2018). 
  11. J. J. Ni, T. Y. Ma, Y. R. Wu, and M. Yan: J. Magn. Magn. Mater. 322(22) (2010) 3710-3713.  https://doi.org/10.1016/j.jmmm.2010.07.031
  12. D. Givord, A. Lienard, R. P. De La Bathie, P. Tenaud, T. Viadieu, Le Journal de Physique Colloques 46(C6) (1985) C6-313-C6-317. 
  13. T. Kawai, B. Ma, S. Sankar, and W. E. Wallace: J. Appl. Phys. 67(9) (1990) 4610-4612.  https://doi.org/10.1063/1.344828
  14. J. D. Livingston: J. Appl. Phys. 57(8) (1985) 4137-4139.  https://doi.org/10.1063/1.334644
  15. M. Yan, L. Q. Yu, W. Luo, W. Wang, W. Y. Zhang, and Y. H. Wen: J. Magn. Magn. Mater. 301(1) (2006) 1-5.  https://doi.org/10.1016/j.jmmm.2005.06.003
  16. T.-H. Kim, S.-R. Lee, S. Namkumg, and T.-S. Jang: J. Alloys Compd. 537 (2012) 261-268.  https://doi.org/10.1016/j.jallcom.2012.05.075
  17. T.-H. Kim, S.-R. Lee, M.-W. Lee, T.-S. Jang, J. W. Kim, Y. D. Kim, and H.-J. Kim: Acta Mater. 66 (2014) 12-21.  https://doi.org/10.1016/j.actamat.2013.11.063
  18. W. F. Li, T. Ohkubo, and K. Hono: Acta Mater. 57(5) (2009) 1337-1346.  https://doi.org/10.1016/j.actamat.2008.11.019
  19. F. Vial, F. Joly, E. Nevalainen, M. Sagawa, K. Hiraga, and K. T. Park: J. Magn. Magn. Mater. 242-245 (2002) 1329-1334. https://doi.org/10.1016/S0304-8853(01)00967-2