Changes of the anisotropy direction in amorphous strips due to annealing in absence of magnetic field and external stresses

An unusual change of the anisotropy direction is observed on square strips of Co-based amorphous alloy of Metglas 2714A. This change is obtained by annealing without any applied magnetic field or external stress. The anisotropy direction moves from its original direction along the ribbon axis to the transverse direction in the strip plane. This occurs when annealing is performed above the Curie temperature. The effect is analysed through the characteristics of hysteresis loops together with measurements of complex permeability and magnetoresistivity and is discussed on the basis of the magnetoelastic behavior of the material and the different structural morphologies of the surface layers of the ribbons.<
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