Magnetic properties and induced anisotropy of nanocrystalline Fe72.5–xNixCu1.1Nb1.9Mo1.5Si14.3B8.7 alloys

Resumo

The effects of the substitution of nickel for iron on the magnetic properties, uniaxial anisotropy induced by magnetic field, and crystallization process of the nanocrystalline Fe_72.5–xNi_xCu_1.1Nb_1.9Mo_1.5Si_14.3B_8.7 FINEMET alloys modified with molybdenum have been studied. Nickel additions of up to 3 at % have been shown to increase the Curie temperature and magnetization of the alloy, whereas nickel additions of more than 6 at % lead to the decrease in these parameters as compared to those for the initial nickel-free alloy. Nickel additions of 6‒7 at % cause a linear increase in the induced uniaxial magnetic anisotropy constant. Nickel additions of more than 6 at % restrain the crystallization of the alloy and lead to substantial decrease in its magnetic hysteresis characteristics.