Magnetic annealing effect in amorphous Fe_100-xB_x and Co_100-xB_x binary alloys

The uniaxial magnetic anisotropy induced by magnetic annealing was studied for rapidly quenched amorphous Fe_100-xB_x (12≤x≤25) and Co_100-xB_x (17≤x≤30) alloys. The value of induced uniaxial anisotropy constant K_ui increased with increasing B content from 1 x 10³ erg/cm³ at x = 12 to about 4 x 10³ erg/cm³ at x = 25 in Fe_100-xB_x alloy s exhibiting an inflection around x=20. While the value of K_ui in Co_100-xB_x alloys exhibits a maximum of about 6 x 10³ erg/cm³ aro round x=20. The compositional dependence of K_ui for both alloy systems can be explained roughly by the model of the directiona; occupation of B atom between ferromagnetic atoms.