한국생산제조학회 학술지 영문 홈페이지
[ 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

김병준a ; 김용성b, * ; 주기태b ; 김준현b ; 박익근b ; 이재용c ; 양수원c
Study on Demagnetization and Magnetization to Reuse NdFeB-based Magnets
Byeong Jun Kima ; Young Sung Kimb, * ; Gi Tae Joob ; Joon Hyun Kimb ; Ik Geun Parkb ; Jae Yong Leec ; Su Won Yangc
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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Byeong Jun Kim

Master Candidate in the Graduate School of NIDE Fusing Technology, Seoul National University of Science and Technology.

His research interest is Material and Nano-Micro Technology.

E-mail: kbj1020@seoultech.ac.kr

Young Sung Kim

Professor in the NDT Research Center, Seoul National University of Science and Technology.

His research interest in Material and Nano-Micro Technology.

E-mail: youngsk@seoultech.ac.kr

Gi Tae Joo

Senior Research in the NDT Research Center, Seoul National University of Science and Technology.

His research interest is Optical Ceramics.

E-mail: gtjoo@seoultech.ac.kr

Joon Hyun Kim

Research Professor in NDT Research Center, Seoul National University of Science and Technology.

His research interest is Tribology.

E-mail: joonk61@seoultech.ac.kr

Ik Keun Park

Professor in the Department of Mechanical&Automotive Engineering, Seoul National University of Science and Technology.

His Research interest is Nondestructive Evaluation.

E-mail: ikpark@seoultech.ac.kr

Jae Yong Lee

Director in Corporate R&D Center, Hanchung R.F.

His research interest is Resource Recycling.

E-mail: 57jylee@naver.com

Su Won Yang

Chief researcher in Corporate R&D Center, Hanchung R.F.

His research interest is Soft magnetic material and Resource Recycling.

E-mail: hcswyang@gmail.com