[ Papers ]

Journal of the Korean Society of Manufacturing Technology Engineers - Vol. 30, No. 4, pp.269-277

ISSN: 2508-5107 (Online)

Print publication date 15 Aug 2021

Received 25 Jun 2021 Revised 06 Jul 2021 Accepted 15 Jul 2021

DOI: https://doi.org/10.7735/ksmte.2021.30.4.269

NdFeB계 자석의 재사용을 위한 탈자 및 착자 연구

김병준^a ; 김용성^b^{, *} ; 주기태^b ; 김준현^b ; 박익근^b ; 이재용^c ; 양수원^c

Study on Demagnetization and Magnetization to Reuse NdFeB-based Magnets

Byeong Jun Kim^a ; Young Sung Kim^b^{, *} ; Gi Tae Joo^b ; Joon Hyun Kim^b ; Ik Geun Park^b ; Jae Yong Lee^c ; Su Won Yang^c

aGraduate School of NIDE Fusing Technology, Seoul National University of Science & Technology
bSeoul Tech NDT Research Center, Seoul National University of Science & Technology
cCorporate R&D Center, Hanchung R.F.

Correspondence to: ^*Tel.: +82-2-970-6804 E-mail address: youngsk@seoultech.ac.kr (Young Sung Kim).

Abstract

In this study, batch-type demagnetization heat-treatment conditions were studied via computational simulations to reuse waste NdFeB-based permanent magnets. t room temperature, the time delay for the Nd magnet specimen to reach the target temperature in the furnace There was a delay in the time required for the temperature of the specimen and the furnace temperature to reach the target temperature. This delay time was observed to decrease from 27 min to 12 min as the heat treatment temperature increased from 100℃ to 400℃. The magnetic fluxes of the Nd magnets decreased with an increase in the heat treatment temperatures, and the magnets demagnetized at 300℃. The completely demagnetized magnet was fully remagnetized when more than 6000 J of magnetizing energy was applied. Further, by analyzing the surface soundness of the demagnetized Nd magnet, it was confirmed that the magnet could be reused.

Keywords:

Reusable, Demagnetization, Remagnetization, NdFeB magnet, Batch type heat treatment

Acknowledgments

이 논문은 2021년도 에너지기술개발사업 과제번호 20205210100070의 연구비지원으로 수행되었습니다.

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