DOMAIN OBSERVATIONS OF FE AND CO BASED AMORPHOUS WIRES

Domain observations were made on Fe and Co based amorphous magnetic wi res that exhibit a large Barkhausen discontinuity during flux reversal . Domain patterns observed on the wire surface were compared with thos e found on a polished section through the center of the wire. It was c onfirmed that the Fe based wire consists of a shell and core region as previously proposed, however, there is a third legion between them. T his fairly thick transition region made up of domains at an angle of a bout 45 degrees to the wire axis clearly lacking the closure domains o f the previous model. The Co based wire does not have a clear core and shell domain structure. The center of the wire had a classic domain s tructure 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 anisotr opy is consistent with the domain patterns in the Fe based wire, howev er, shape anisotropy still plays a dominant role in defining the wire core in the Co based wire.