Title :
Topology of Nd-Fe-B magnets with a high energy density
Author :
Rodewald, W. ; Wall, B. ; Katter, M. ; Uestuener, K.
Author_Institution :
Vacuumschmelze GmbH & Co. KG, Hanau, Germany
Abstract :
The topology and the effect of the B-content on the grain growth rate of sintered Nd-Fe-B magnets has been examined. Most of the grains have 5-6 corners. Normal grains grow slowly for B-contents <5.7 at.%, but grow faster for higher B-contents. Abnormal large grains grow almost as fast as grains in pure metals. By optimizing the composition and refining the processing route sintered Nd-Fe-B magnets with a remanence of 1.528 T, a coercivity HcJ of 840 kA/m (10.6 kOe) and a maximum energy density of 454 kJ/m3 (57 MGOe) could be prepared.
Keywords :
boron alloys; coercive force; demagnetisation; ferromagnetic materials; grain growth; iron alloys; neodymium alloys; permanent magnets; powder metallurgy; remanence; sintering; B-content; Nd-Fe-B; abnormal large grains; coercivity; composition optimization; demagnetization curves; grain growth rate; high energy density; maximum energy density; processing route refining; remanence; sintered Nd-Fe-B magnets; topology; Coercive force; Demagnetization; Iron alloys; Magnetic properties; Magnets; Microstructure; Neodymium; Polarization; Powders; Topology;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2003.815750
