Domain structure of chemically thinned Fe-Si-B amorphous wires

In this study, we investigate the change in the magnetic properties of magnetostrictive Fe_77.5Si_7.5B₁₅ amorphous wires thinned by chemical etching focusing on domain structure. It is found that the re-entrant flux reversal characteristic is still maintained even in the wire chemically thinned to a diameter of 27 μm. The maze domain is observed on the wire thinned to a diameter of around 80 μm. Below this diameter, the wire shows bamboo domains. When thinned below 42 μm, the wire shows the single domain. The drastic change in the domain configuration due to thinning is explained by considering the very low anisotropy in the thinned wire caused by the decrease of anisotropy due to the etching of the outer shell. It is confirmed that the domain structure of the as-quenched 65 μm wire is quite different from that of the wire thinned to the same diameter