Neutron irradiation study of Nd-Fe-B permanent magnets made from melt-spun ribbons

Journal Article · Tue Nov 15 00:00:00 EST 1988 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.342400· OSTI ID:6749642

Brown, R D; Cost, J R; Meisner, G P; Brewer, E G

Radiation-induced changes in the magnetization of sintered Nd-Fe-B permanent magnets are known to vary widely among specimens produced by different manufacturers. Samples of Nd-Fe-B MAGNEQUENCH magnets, which are made from melt-spun ribbons, have not been studied and show a much reduced sensitivity to neutron irradiation than do sintered Nd-Fe-B magnets. All melt-spun ribbon-based MAGNEQUENCH magnets, i.e., epoxy-bonded, hot-pressed, and die-upset magnets, show essentially the same slow decrease in magnetic remanence with neutron dose. Measurements of the open-circuit remanence B/sub r//B/sub r//sub //sub 0/ at various times during the irradiation show a decay of only 1.5% of the preirradiated value for the MAGNEQUENCH magnets after 1 h of irradiation, or a dose of 1.4 x 10/sup 16/ neutrons/cm/sup 2/, compared to a 4.6% drop in remanence for the best sintered Nd-Fe-B magnet (Sumitomo 30H) with the same irradiation dose. Moreover, after 5.3 h of irradiation, the remanence drops by only 3% for the MAGNEQUENCH magnets. Magnets made from melt-spun ribbons are thus the least sensitive to neutron irradiation so far measured for Nd-Fe-B permanent magnets, but are somewhat more sensitive than samarium-cobalt magnets.

• Research Organization: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
• OSTI ID: 6749642
• Journal Information: J. Appl. Phys.; (United States), Vol. 64:10
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BORON ALLOYS
MAGNETIC PROPERTIES
PHYSICAL RADIATION EFFECTS
IRON ALLOYS
NEODYMIUM ALLOYS
COERCIVE FORCE
DOMAIN STRUCTURE
EXTRUSION
HOT PRESSING
MAGNETIZATION
PERMANENT MAGNETS
THERMAL NEUTRONS
ALLOYS
BARYONS
ELEMENTARY PARTICLES
FABRICATION
FERMIONS
HADRONS
MAGNETS
MATERIALS WORKING
NEUTRONS
NUCLEONS
PHYSICAL PROPERTIES
PRESSING
RADIATION EFFECTS
RARE EARTH ALLOYS
360106* - Metals & Alloys- Radiation Effects