Enhanced magnetoimpedance and field sensitivity in microstructure controlled FeSiCuNbB ribbons

Abstract

Giant magnetoimpedance effect in ultrasoft FeAlSiBCuNb nanocomposites for sensor applications J. Appl. Phys. 98, 014316 (2005); 10.1063/1.1953864 Valve behavior of giant magnetoimpedance in field-annealed Co 70 Fe 5 Si 15 Nb 2.2 Cu 0.8 B 7 amorphous ribbon nanocomposite materials consisting of nanocrystalline phase in an amorphous matrix were obtained by heat-treatment of their precursor amorphous ribbons. The influence of structural modifications induced during the heat-treatment on soft magnetic properties and magnetoimpedance (MI) effect have been studied. The structural investigations on both these ribbons revealed the presence of two phases, fine grained Fe 3 Si phase and a residual amorphous phase on heat-treatment. The maximum MI ratio obtained in the present study is 95% at f ¼ 4 MHz, for the optimized heat-treated Fe 77.2 Si 11.2 Cu 0.8 Nb 3.3 B 7.5 ribbon. This is ascribed to the increase in magnetic permeability and decrease in coercive force and intrinsic resistivity. Moreover, a maximum magnetic field sensitivity (n) of 8.3%/Oe at f ¼ 2.5 MHz is obtained, for the optimized nanocrystalline Fe 73.5 Si 13.5 Cu 1 Nb 3 B 9 ribbon. This suggests that tailoring of the nanocrystalline microstructures induced by optimum heat-treatment conditions can result in obtaining excellent combinations of the magnetic permeability and resistivity. Our results indicate that these Fe-based nanocrystalline materials can be ideally used for low magnetic field and high frequency sensor applications.

Magnetoimpedance effect in nanocrystalline Fe73.5Cu1Nb3Si13.5B9 single-layer and bilayer ribbons

“…This different behavior is due to various thicknesses of the ribbons, as we have explained before. The obtained high magnetic field sensitivity of our ribbons compares favorably with the previous results reported by other groups [19,40,41], which makes them prospective materials for potential magnetic sensors applications [19,20].…”

Tailoring Magnetic Properties and Magnetoimpedance Response in Nanocrystalline (Fe3Ni)81Nb7B12 Ribbons for Sensor Applications

“…Particularly, the TFA ribbons can reach field sensitivities as high as 200%/(kA/m) in the field range 225-575 A/m at 3 MHz. This field-sensitivity value is larger than previous reported values in Fe systems [65,66]. In addition, in Figure 5a, it is observed that the maximum field sensitivity is reduced from 80 MHz for the as-cast sample to the frequency range of 1-5 MHz for the annealed samples.…”

Giant Magnetoimpedance in Fe_73.5Cu₁Nb₂V₁Si_13.5B₉Nanocrystalline Ribbons

“…6.It shows that the effective inductance for the sample annealed at 550°C is highest among all annealed samples. The relative permeability dependence on the annealing temperature for FeCuNbSiB ribbons was also estimated [13]. The frequency dependence of relative permeability ∆µ'/µ'=µ'(90 Oe)-µ'(0)]/µ'(90 Oe) for Fe 73.5 Cu 1 Nb 2 VSi 13.5 B 9 annealed at 550°C is shown in Fig.…”