Nanostructuring effects in soft magnetic films and film elements with magnetic impedance

The magnetization reversal and magnetic impedance (MI) of films and film elements based on Fe19Ni81 and Fe72. 5Cu1. 1Nb1. 9Mo1. 5Si14. 2B8. 7 alloys with a varied thickness, heat-treatment temperature, and the number of thin Cu interlayers are studied. The dependences of the coercive force and the magnitude of MI on these parameters are found. Layered structuring is shown to be an effective method for improving the functional characteristics of MI elements. In elements containing nanocrystalline Fe19Ni81 layers, this is related to the restructuring of a magnetic structure; in elements containing amorphous Fe72. 5Cu1. 1Nb1. 9Mo1. 5Si14. 2B8. 7 layers, this improvement is likely to be caused by a decrease in the effective electrical resistivity. © 2013 Pleiades Publishing, Ltd

Magnetoimpedance and stress-impedance effects in amorphous CoFeSiB ribbons at elevated temperatures

The temperature dependencies of magnetoimpedance (MI) and stress impedance (SI) were analyzed both in the as-quenched soft magnetic Co68.5Fe4Si15B12.5 ribbons and after their heat treatment at 425 K for 8 h. It was found that MI shows weak changes under the influence of mechanical stresses in the temperature range of 295-325 K and SI does not exceed 10%. At higher temperatures, the MI changes significantly under the influence of mechanical stresses, and SI variations reach 30%. Changes in the magnetoelastic properties for the different temperatures were taken into consideration for the discussion of the observed MI and SI responses. The solutions for the problem of thermal stability of the magnetic sensors working on the principles of MI or SI were discussed taking into account the joint contributions of the temperature and the applied mechanical stresses. © 2020 by the authors.KK-2019/00101Funding: This work was supported in part by the Basque Country government under Elkartek program, grant KK-2019/00101