Dynamic studies of magnetic domains using a Hall probe scanner

A Hall probe scanner has been developed capable of imaging both static and dynamic magnetic domains at the macroscopic scale. The technique is non-destructive and measures the perpendicular stray field component of magnetization associated with the small misalignment of magnetic domains with respect to the material's surface. The scanner has clearly demonstrated its capability to image magnetic domains under the surface coating of grain oriented electrical steel. Stroboscopic observations at magnetizing frequencies up to 100 Hz have yielded well defined domain images for high permeability grain oriented steel samples magnetized to 1.0 T. This technique now offers the possibility to study the magnetization dynamics in coated electrical steel which cannot be easily achieved with conventional imaging methods