Original scientific paper
Influence of the successive annealing on the magnetization processes in Fe73.5Cu1Nb3Si15.5B7 ribbon
Stjepan Sabolek
; Department of Physics, Faculty of Science, University of Zagreb, POB 162, Zagreb, Croatia
Željko Marohnić
; Institute of Physics of the University, University of Zagreb, POB 304, Zagreb, Croatia
Giselher Herzer
; Vacuumschmelze GmbH, D-63450 Hanau, Germany
Abstract
The model for the influence of core–current generated field Hp on the magnetization processes in ferromagnetic ribbons has been employed for the detailed analysis of the M − H loops and the corresponding dM/dt vs. H curves for Fe73.5Cu1Nb3Si15.5B7 alloy, successively annealed at different temperatures Ta ≤ 540 ◦C. The analysis shows that in the amorphous state (Ta ≤ 300 ◦C), only fraction of the main (inner) domain structure participates in the process of magnetization. Further annealing strongly reduces the local anisotropy and the average pinning strength of the domain walls < Su >, which results in a very low coercive field Hc for 400 ◦C ≤ Ta ≤ 500 ◦C. Simultaneously, the maximum magnetization Mm becomes almost equal to the saturation magnetization Ms (≈ 1.3 T) already in low magnetizing field (H0 = 100 A/m). The minimum of Hc (Ta = 450 ◦C) is associated with the formation of nanocrystalline Fe3Si grains, and high Mm and maximum permeability µmax and a low angle < δ > (between domain magnetizations and the ribbon axis) show that a whole domain structure is very simple in this range of Ta. Further annealing (Ta > 500 ◦C) increases < Su > and < δ > (which increases Hc) and reduces drastically µmax which is consistent with the earlier results for similar samples.
Keywords
Hrčak ID:
299617
URI
Publication date:
1.10.1996.
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