Abstract
The derivative of the magnetization with time (dM/dt) as a function of the applied magnetic field (H) has been measured for Co74Fe6B20 amorphous ribbons. The samples of the alloy have been prepared by melt-spinning in vacuum (S) and in argon atmosphere (R). The peculiar hysteresis curves obtained indicate that the process of domain wall stabilization occurs in both samples. This process manifests itself through a sharp change of magnetization (300 Ts−1 for sample S) when the domain wall releases itself from the stable position. A smaller value of dM/dt observed for sample R indicates that the actual preparation conditions affect domain wall stabilization. An additional d.c. field, H p, (caused by current flow through the sample) changes dM/dt as well as the value of the magnetic field required to release the domain wall from its stable position (H s) All the observed variations of dM/dt versus H with H p as a parameter can be explained by assuming that the magnetization of the domains is not exactly collinear with the long axis of the ribbons and that the strengths of the domain wall stabilization at different surfaces of the sample (free and contact surface) are not the same. A model which explains the observed phenomena is proposed.