Magnetoelastic Acoustic Emission in Ferromagnetic Materials. I. Effect of Crystal Anisotropy

The paper considers the relation between the parameters of magnetoelastic acoustic emission (MAE) on one side and the magnitude of longitudinal magnetostriction and the behavior of magnetic domain structure on the other, i.e., effects of irreducible displacements of 90° (71° and 109°) domain walls when the magnetization is aligned with various crystal axes in crystals of siliceous iron and nickel. The MAE parameters are controlled by processes of reshaping of magnetic domains, therefore they are highly susceptible to the crystallographic orientation of the material. In samples of various shapes (strips and disks), a linear relation between the MAE parameters and the resulting magnetostriction in the region of low fields (where domain walls are displaced) was detected, but there is no linear relation in the region of higher fields, where the role of reversible and irreversible processes of magnetization rotation is greater.