Title :
Temperature compensation of NdFeB permanent magnets
Author :
Kim, S.H. ; Doose, C.
Author_Institution :
Adv. Photon Source, Argonne Nat. Lab., IL, USA
Abstract :
Permanent magnet blocks of NdFeB have a relatively high maximum energy product. Because of its relatively low Curie temperature, however, NdFeB has a large temperature coefficient for its residual induction. The temperature coefficients of the relative magnetic fields (ΔB/B)/ΔT in the air gap of NdFeB dipole magnets were reduced from -1.1×10-3/°C to less than 2×10 -5/°C under operating temperatures of ±6°C. This was achieved passively by using 1.25-mm-thick strips of 30%-Ni-Fe alloy as flux shunts for the NdFeB blocks. The magnets with soft-steel poles and flux-return yokes were assembled and measured in a temperature-controlled environment
Keywords :
accelerator magnets; boron alloys; iron alloys; neodymium alloys; permanent magnets; storage rings; Curie temperature; NdFeB; NdFeB permanent magnets; flux-return yokes; operating temperatures; permanent magnet blocks; relative magnetic fields; residual induction; soft-steel poles; temperature compensation; temperature-controlled environment; Ferrites; Magnetic field measurement; Magnetic fields; Magnetic flux; Magnetization; Permanent magnets; Permeability; Strips; Temperature distribution; Temperature sensors;
Conference_Titel :
Particle Accelerator Conference, 1997. Proceedings of the 1997
Conference_Location :
Vancouver, BC
Print_ISBN :
0-7803-4376-X
DOI :
10.1109/PAC.1997.753163
