Title :
Hysteresis behavior and microstructure of exchange coupled R2 Fe14B1/α-Fe magnets
Author :
Withanawasam, L. ; Murthy, A.S. ; Hadjipanayis, G.C.
Author_Institution :
Dept. of Phys. & Astron., Delaware Univ., Newark, DE, USA
fDate :
11/1/1995 12:00:00 AM
Abstract :
The hysteresis behavior of nanocomposite R2Fe14 B/α-Fe magnets with R=Nd and Pr was investigated at low temperatures. The room temperature coercivity depends on annealing with a peak value at 700°C. The low coercivity of samples annealed at temperatures below the optimum is due to incomplete transformation of R 3Fe62B14 to R2Fe14B phase. Hysteresis loops of Pr2Fe14B/α-Fe samples change from a smooth to a constricted loop when temperature is varied from 300 to 10 K. This may be due to the decoupling of a fraction of the larger 2:14:1 grains which reverse independently of the rest of the sample
Keywords :
annealing; boron alloys; coercive force; composite materials; crystal microstructure; ferromagnetic materials; iron; iron alloys; magnetic hysteresis; magnetic particles; magnetisation reversal; nanostructured materials; neodymium alloys; permanent magnets; praseodymium alloys; remanence; 10 to 300 K; 20 C; 2:14:1 grains; 700 C; Fe; Nd2Fe14B; Pr2Fe14B; Pr2Fe14B/α-Fe samples; R2Fe14B phase; R3Fe62B14; annealing; constricted loop; decoupling; exchange coupled R2Fe14B1/α-Fe magnets; hysteresis behavior; hysteresis loops; incomplete transformation; low coercivity; low temperature; microstructure; nanocomposite R2Fe14B/α-Fe magnets; room temperature coercivity; Annealing; Coercive force; Iron; Magnetic anisotropy; Magnetic hysteresis; Magnetic materials; Magnets; Microstructure; Soft magnetic materials; Temperature dependence;
Journal_Title :
Magnetics, IEEE Transactions on
