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Title: Rare earth magnets resisting eddy currents

Abstract

Magnets with high electrical resistance were prepared by electrically isolating Sm{sub 2}Co{sub 17} and Nd{sub 2}Fe{sub 14}B powder particles. It is done by a polymer mixture consisting of epoxy polyester-insulant (EPI), polyvinylbutyral (PVB), epoxy resin (ER) and silane coupling (SC). The properties of interest for anisotropic Sm{sub 2}Co{sub 17} and isotropic Nd{sub 2}Fe{sub 14}B magnets respectively are {rho} = 1 x 10{sup 5} {Omega} {minus}cm{sup 2}/m, Br = 6.8 kGs, {sub 1}H{sub c} = 10.0 kOe, (BH){sub max} = 9.2 MGOe in 5% EPI, 4%PVB, 2%ER, 1%SC and {rho} = 9.4 x 10{sup 4} {Omega} {minus}cm{sup 2}/m, Br = 4.5kG, {sub i}H{sub c} = 9.5 kOe, (BH){sub max} = 4.3 MGOe in 4%EPI, 3%PVB, 2% ER, 1%SC. The insulated magnets exhibit far better magnetic stability than those of sintered and bonded magnets after magnetizing in radio frequency. The insulated Sm{sub 2}Co{sub 17} magnet has the best performance in resisting eddy current. In 500 kHz frequency, 830 Oe magnetizing-field and in one minute, the irreversible loss of recoil remanence is 1.47% and 22.2% respectively for insulated Sm{sub 2}Co{sub 17} and Nd{sub 2}Fe{sub 14}B magnets.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Central Iron and Steel Research Inst., Beijing (CN)
OSTI Identifier:
20000769
Resource Type:
Journal Article
Journal Name:
IEEE Transactions on Magnetics (Institute of Electrical and Electronics Engineers)
Additional Journal Information:
Journal Volume: 35; Journal Issue: 5Pt2; Conference: 1999 international magnetics conference (Intermag '99), Kyongju (KR), 05/18/1999--05/21/1999; Other Information: PBD: Sep 1999; Journal ID: ISSN 0018-9464
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ELECTRIC CONDUCTIVITY; MAGNETIC PROPERTIES; EDDY CURRENTS; SAMARIUM ALLOYS; COBALT BASE ALLOYS; IRON BASE ALLOYS; NEODYMIUM ALLOYS; BORON ALLOYS; PERMANENT MAGNETS

Citation Formats

Pan, W., Li, W., Cui, L.Y., Li, X.M., and Guo, Z.H. Rare earth magnets resisting eddy currents. United States: N. p., 1999. Web. doi:10.1109/20.800519.
Pan, W., Li, W., Cui, L.Y., Li, X.M., & Guo, Z.H. Rare earth magnets resisting eddy currents. United States. doi:10.1109/20.800519.
Pan, W., Li, W., Cui, L.Y., Li, X.M., and Guo, Z.H. Wed . "Rare earth magnets resisting eddy currents". United States. doi:10.1109/20.800519.
@article{osti_20000769,
title = {Rare earth magnets resisting eddy currents},
author = {Pan, W. and Li, W. and Cui, L.Y. and Li, X.M. and Guo, Z.H.},
abstractNote = {Magnets with high electrical resistance were prepared by electrically isolating Sm{sub 2}Co{sub 17} and Nd{sub 2}Fe{sub 14}B powder particles. It is done by a polymer mixture consisting of epoxy polyester-insulant (EPI), polyvinylbutyral (PVB), epoxy resin (ER) and silane coupling (SC). The properties of interest for anisotropic Sm{sub 2}Co{sub 17} and isotropic Nd{sub 2}Fe{sub 14}B magnets respectively are {rho} = 1 x 10{sup 5} {Omega} {minus}cm{sup 2}/m, Br = 6.8 kGs, {sub 1}H{sub c} = 10.0 kOe, (BH){sub max} = 9.2 MGOe in 5% EPI, 4%PVB, 2%ER, 1%SC and {rho} = 9.4 x 10{sup 4} {Omega} {minus}cm{sup 2}/m, Br = 4.5kG, {sub i}H{sub c} = 9.5 kOe, (BH){sub max} = 4.3 MGOe in 4%EPI, 3%PVB, 2% ER, 1%SC. The insulated magnets exhibit far better magnetic stability than those of sintered and bonded magnets after magnetizing in radio frequency. The insulated Sm{sub 2}Co{sub 17} magnet has the best performance in resisting eddy current. In 500 kHz frequency, 830 Oe magnetizing-field and in one minute, the irreversible loss of recoil remanence is 1.47% and 22.2% respectively for insulated Sm{sub 2}Co{sub 17} and Nd{sub 2}Fe{sub 14}B magnets.},
doi = {10.1109/20.800519},
journal = {IEEE Transactions on Magnetics (Institute of Electrical and Electronics Engineers)},
issn = {0018-9464},
number = 5Pt2,
volume = 35,
place = {United States},
year = {1999},
month = {9}
}