Stabilization and destabilization of domain wall positions in Fe-Si polycrystals using magnetic annealing effects

The effect of variation of magnetic annealing conditions on the properties of grain-oriented Fe-3%Si steels was investigated. It was shown that during magnetic annealing with special magnetizing conditions (in the B-range, corresponding to the stability of a large number of 90 degrees-supplementary domains), the special magnetic structure is stabilized. This state is characterized by the increase of the sample magnetostriction in low and high fields as well as under compression, demonstrating the increased contribution of 90 degrees-domain wall displacements and the magnetic domain structure rearrangement. The initial material state may be recovered using magnetic reannealing in the AC held by means of destabilization of induced changes in structure. Magnetic annealing in high DC fields yields an increase of preferred alignment of magnetic domains along the rolling direction and a pronounced magnetostriction decrease. (C) 1998 Elsevier Science B.V. All rights reserved.