ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
The amorphous state of ferromagnetic Fe83B9Nb7Cu1 and its nanocrystallization have been studied by x-ray, Mössbauer spectroscopy, and magnetic moment measurements. In the amorphous state at 13 K, the Mössbauer spectrum exhibits an essentially symmetric hyperfine field distribution with a half-width of 72 kOe. The average hyperfine field Hhf(T) of the amorphous state shows a temperature dependence of [Hhf(T)−Hhf(O)]/Hhf(O)=−0.48(T/TC)3/2 u −0.22(T/TC)5/2 for T/TC〈0.7, indicative of spin-wave excitation. The quadrupole splitting just above the Curie temperature TC is 0.43 mm/s, whereas the average quadrupole shift below TC is zero. The Curie and crystallization temperatures are determined to be TC=393 K and Tx=775 K, respectively, for a heating rate of 5 K/min. The occupied area of the nanocrystalline phase at the optimum annealing temperature is about 33%–71%. It is notable that the magnetization of the amorphous phase decreases more rapidly with reduced temperature than those of nanocrystalline ferromagnets, suggesting the presence of the distribution of exchange interactions in the amorphous phase or high metalloid contents. © 1996 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.362337
