Effects of neutron irradiation on Nd-Fe-B magnetic properties

Journal Article · Sun May 01 00:00:00 EDT 1988 · IEEE Trans. Magn.; (United States)

DOI:https://doi.org/10.1109/20.3393· OSTI ID:6229938

Cost, J R; Brown, R D; Giorgi, A L; Stanely, J T

Nd-Fe-B permanent magnets from two different manufacturers were irradiated in the Omega West Reactor at Los Alamos National Laboratory, Los Alamos, NM, with fast neutrons at temperatures of 426 K (153/sup 0/C) and 350 K (77/sup 0/C) to fluences of 5.0 x 10/sup 16/ N/cm/sup 2/ and 6.1 x 10/sup 16/ N/cm/sup 2/, respectively. At intervals during the irradiation the samples were removed from the reactor and the remanence measured at room temperature. The initial loss of remanence for irradaition at 426 K was ten percent for a fluence of 10/sup 15/ N/cm/sup 2/. At 350 K the initial loss rate was roughly half this value. The loss rates were nearly the same for samples from the two different manufacturers. These losses are due to the irradiation since the remanence does not decay with annealing at 426 K. Remagnetization after irradiation results in full recovery of the remanence and roughly a 20-percent increase in the coercivity. Evidence from this experiment suggests that the primary mechanism for loss of remanence is nucleation of reverse domains by the collision cascade and subsequent growth into the original domain.

• Research Organization: Los Alamos National Labs., Los Alamos, NM (US)
• OSTI ID: 6229938
• Journal Information: IEEE Trans. Magn.; (United States), Vol. 24:3
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BORON ALLOYS
MAGNETIC PROPERTIES
PHYSICAL RADIATION EFFECTS
IRON ALLOYS
NEODYMIUM ALLOYS
PERMANENT MAGNETS
EXPERIMENTAL DATA
IRRADIATION
NEUTRON DIFFRACTION
TERNARY ALLOY SYSTEMS
ALLOY SYSTEMS
ALLOYS
COHERENT SCATTERING
DATA
DIFFRACTION
INFORMATION
MAGNETS
NUMERICAL DATA
PHYSICAL PROPERTIES
RADIATION EFFECTS
RARE EARTH ALLOYS
SCATTERING
360106* - Metals & Alloys- Radiation Effects