Effect of composite magnetic annealing in amorphous alloys

Fe79B15.5Si3.5C2amorphous alloy ribbons with width of 10 mm were prepared by a single roller quenching technique. The samples were made as teroids which were insulated by MgO between layers. At first the transverse magnetic annealing was carried out at 400°C in a solenoid. Subsequently the annealed samples were once more annealed in a DC longitudinal magnetic field at 260°C-320°C for 10 minutes. We annealed the samples at different temperatures until the cumulative exposure was over 200 minutes. The combination of the transverse magnetic annealing and the longitudinal magnetic annealing is called composite magnetic annealing. It is a new method. Using the method, the residual magnetic flux density Br can be controlled easily. The loss Pc and the exciting power Pe can be controlled to obtain a proper ratio.