Magnetostriction behavior in isotropic and cube-on-face 3% SiFe laminations

Abstract

The anomalous negative magnetostriction elongation Δl/l previously observed on Goss texture sheets, associated with the formation during magnetization of transverse spike domains, has been investigated in non-oriented and cube-on-face 3% SiFe laminations. On isotropic sheets, the appearance of a negative Δl/l peak, centered at relatively high inductions B, is essentially masqued by the positive contribution due to the reorientation of a main domain structure, containing many regions whose magnetization forms large angles, up to 90°, with respect to the sheet axis. However, upon application of a tensile stress, a large fraction of these domains can be suppressed and a negative magnetostriction peak appears. The effect is identically observed on cube-on-face laminations. These results show that the presence of an anomalous negative magnetostriction peak is a general phenomenon, not limited to the case of Goss texture laminations. Therefore the formation of transverse spike domains at intermediate inductions is shown to characterize the magnetization process also in isotropic and cube-on-face 3% SiFe materials.