Domain observations of Fe and Co based amorphous wires

Domain observations were made on Fe- and Co-based amorphous magnetic wires that exhibit a large Barkhausen discontinuity during flux reversal. Domain patterns observed on the wire surface were compared with those found on a polished section through the center of the wire. It was found that the Fe-based wire consists of a shell and core region with a third region between them. This fairly thick transition region made up of domains at an angle of about 45° to the wire axis lacks the closure domains of the previous model. The Co-based wire does not have a clear core and shell domain structure. The center of the wire has a classic domain structure expected of uniaxial anisotropy with the easy axis normal to the wire axis. When a model for the residual stress quenched-in during cooling of large Fe bars is applied to the wire, the expected anisotropy is consistent with the domain patterns in the Fe-based wire