Influence of exchange energy and magnetic anisotropy on the nanocrystalline alloy

We have studied the influence of exchange energy and magnetic anisotropy on the magnetic properties of nanocrystalline materials. Amorphous ribbons of composition Fe88Zr7B4Cu1 have been annealed between about 500 and 700 degree C. Temperature dependence of magnetization was carried out and nanocrystallized magnetic entities were investigated using the mean field theory and random anisotropy model obtained ferromagnetic correlation length and magneto-crystalline anisotropy constant. The best soft magnetic properties were observed annealed at 650 degree C for the smallest magneto-crystalline anisotropy constant (K1) of about 1.40x104 erg/cm3. We obtained average magnetic anisotropy of 0.81 erg/cm3 which is almost negligible compared with K1 at an annealing temperature of 650 degree C. The local magneto-crystalline anisotropy is randomly averaged out by strong exchange interaction so that this mechanism provides the basis for the good soft magnetic properties. copyright 1997 American Institute of Physics