Anisotropy study of grain oriented steels with Magnetic Barkhausen Noise

Grain oriented electrical steels present strong anisotropy, due to a {110} < 001 > texture (Goss), with [100] direction parallel to rolling direction (RD) and [110] direction parallel to transverse direction (TD). MBN (Magnetic Barkhausen Noise) were employed to measure magnetic properties in several angles towards RD using a 15 degrees step. For 90 degrees to the rolling direction (i.e., TD), the MBN signal changes, decreasing the MBN(rms). It is found a connection between initial permeability and MBNrms. The lower initial permeability for the TD is related to a larger contribution of irreversible rotation in the hysteresis. The MBN procedure is non-destructive and provides rapid understanding of the anisotropy of the material, without the use of laborious methods like Epstein frame or toroidal coils.