Giant Magnetoimpedance in Fe_74.5−xCu_xNb_1.5V_1.5Si_13.5B₉ As-Quenched Ribbons

Abstract

In this work, large values of magnetoimpedance from Fe_74.5−xCu_xNb_1.5V_1.5Si_13.5B₉ as-quenched ribbons is reported. With increasing Cu content, the magnetoimpedance first increases, undergoes a maximum value at x=3.5, and then drops at higher Cu contents. The magnetoimpedance ΔZ⁄Z₀ for the Fe₇₁Cu_3.5Nb_1.5V_1.5Si_13.5B₉ (x=3.5) as-quenched ribbon reaches −31.3% under a field of H=7162 A/m at 1.2 MHz. The grain size of α-Fe(Si) for as-quenched Fe₇₁Cu_3.5Nb_1.5V_1.5Si_13.5B₉ (x=3.5) ribbon is estimated as 14–16 nm. Results show that nanocrystalline Fe-Cu-(Nb,V)-Si-B ribbons with giant magnetoimpedance can be prepared directly from the melt–spinning technique without annealing.