Structural and magnetic anisotropy of directionally-crystallized ferromagnetic microwires

Amorphous ferromagnetic microwires have drawn attention primarily due to their excellent soft magnetic properties as the elements of sensors. In this work, semi-hard magnetic microwires of composition Fe4.3Co67.7Si11B14Cr3 were obtained after a process of directional crystallization from amorphous state. The XRD analysis of crushed and whole wires identified the formation of the face-centered Co-modification as the main phase of directionally crystallized core alloy, which explains a large increase in anisotropy and coercivity. The application of a magnetic field during crystallization may orient the easy anisotropy axis of crystallites along the wire. This is confirmed by the investigation of crystallite orientation with respect to the wire axis and X-rays direction in diffractometer. The obtained results revealed that the formation of crystallites in amorphous Co-rich microwires occurs with the predominant orientation of the crystallographic direction [111] along the wire axis and the direction of a magnetic field during the directional crystallization process.