Effect of annealing on the microstructure of sintered Nd-Fe-B magnets

Journal Article · Sat Mar 15 04:00:00 EST 1986 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.336366· OSTI ID:6122989

Mishra, R K; Chen, J K; Thomas, G

A transmission electron microscopy study of sintered Nd-Fe-B magnets after annealing above 650 /sup 0/C shows the formation of a thin intergranular Nd-rich layer extending to pockets of polycrystalline fcc Nd crystals. The grain boundary phase acts as a pinning site for the magnetic domain walls and is necessary for good magnetic hardening. On the other hand, the Nd/sub 1+epsilon/Fe/sub 4/B/sub 4/ phase is an unavoidable product of the sintering process but need not be present for good coercivity.

• Research Organization: Department of Materials Science and Mineral Engineering and the Materials and Molecular Research Division, Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6122989
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 59:6; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101 -- Metals & Alloys-- Preparation & Fabrication
360102* -- Metals & Alloys-- Structure & Phase Studies
360104 -- Metals & Alloys-- Physical Properties
ALLOYS
ANNEALING
BORON ALLOYS
COERCIVE FORCE
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CRYSTAL-PHASE TRANSFORMATIONS
CRYSTALS
CUBIC LATTICES
DOMAIN STRUCTURE
ELECTRON MICROSCOPY
FABRICATION
FCC LATTICES
GRAIN BOUNDARIES
HEAT TREATMENTS
IRON ALLOYS
MAGNETIC FLUX
MAGNETS
MICROSCOPY
MICROSTRUCTURE
NEODYMIUM ALLOYS
PHASE TRANSFORMATIONS
POLYCRYSTALS
RARE EARTH ALLOYS
SINTERING
TRANSMISSION ELECTRON MICROSCOPY
VERY HIGH TEMPERATURE