Effects of Surface Abrasion on Magnetization of VITROVAC 6025Z Ribbons

The effects of abrading with sandpaper the surface of VITROVAC 6025Z ribbons on the parameters of their M -H loops (the coercive field Hc , the position of the center C, etc.) have been investigated. The application of surface fields HP (generated by core currents) enabled us to single out the effects of surface domains (surface domain structure (SDS) pinning) and surface irregularities (intrinsic pinning) on domain wall (DW) pinning in abraded and unabraded ribbons. The abrasion enhances the intrinsic DW pinning (increases Hc) and strongly modifies the SDS pinning which shows up in specific variations of Hc and C with HP. In particular, the effect of HP on surface domain structure (SDS) pinning, which was symmetrical in unabraded ribbon becomes asymmetrical upon abrasion (i.e., different on opposite surfaces). A simple model for the influence of HP on magnetization processes in soft magnetic ribbons describes the observed variations of Hc and C with HP in both abraded and unabraded ribbons. The use of abrasion in order to tune the effects of oblique fields on M-H loops is briefly discussed.