Stress dependence of magnetization processes:: Reversals and relaxation in FexCo85-xB15 amorphous ribbons -: art. no. 094427

The effect of stress on the domain-wall dynamics fur magnetization reversal and relaxation in FexCo85-xB15 amorphous ribbons was investigated by inductance voltage measurements in the absence of applied field after pulse saturating the sample. Optical Kerr-effect and three-dimensional neutron depolarization experiments have been exploited. Residual domains at pinning sites are the main sources of the domains of reversed magnetization. Such a reversal is driven by an internal field through the motion of more than two walls, nucleated at residual domains and/or ribbon edges, and propagating towards the ribbon center. The number of active walls depends on the regularity of the domain structure. An external tensile stress decreases the voltage induced by the change of the magnetization of the sample and delays the ''depinning time t(c)" of the reverse domain walls. A modified Landau-Lifshitz equation was used to interpret the stress dependence of the magnetization reversal and relaxation. We found that t(c) is proportional to the coercive field, confirming the validity of the proposed model.