Title :
Preparation and TEM-study of sintered Nd18Fe74B6Ga1Nb1 magnets
Author :
Bernardi, Johannes ; Fidler, Josef ; Seeger, Michael ; Kronmuller, H.
Author_Institution :
Inst. of Appl. & Tech. Phys., Tech. Univ., Vienna, Austria
fDate :
11/1/1993 12:00:00 AM
Abstract :
Ga-doped Nd-Fe-B sintered magnets show an improved wetting behavior of the liquid phase during sintering and the formation of additional Ga-containing intergranular phases. Nb forms precipitates within the hard magnetic grains and enhances the coercivity. In the as-sintered magnets, a new Nd-rich Ga-containing region which contains Nd3Ga and Nd5Ga3 is found. This region is formed from the liquid phase during cooling. In addition, the δ-phase occurs in the annealed magnets. Nb is found in the hexagonal NbFeB intergranular boride and in small Nb-containing precipitates within the hard magnetic phase. There is no Nb detected in the Nd-rich phases
Keywords :
annealing; boron alloys; coercive force; crystal microstructure; ferromagnetic properties of substances; gallium alloys; iron alloys; neodymium alloys; niobium alloys; permanent magnets; precipitation; sintering; transmission electron microscope examination of materials; wetting; Ga-containing intergranular phases; Nd18Fe74B6GaNb; TEM-study; annealed magnets; as-sintered magnets; coercivity; delta -phase; hard magnetic grains; hexagonal NbFeB intergranular boride; liquid phase; precipitates; sintered Nd18Fe74B6Ga1Nb1 magnets; sintering; wetting behavior; Annealing; Diffraction; Electrons; Iron; Magnets; Neodymium; Niobium; Phase detection; X-ray detection; X-ray detectors;
Journal_Title :
Magnetics, IEEE Transactions on
