Structure and Magnetic Properties of As-Quenched Fe_87−xZr_3.5Nb_3.5B₆Cu_x Ribbons

Abstract

The influences of Cu addition upon structure and magnetic properties of as-quenched Fe_87−xZr_3.5Nb_3.5B₆Cu_x ribbons are investigated. An appropriate content of Cu addition improves the nucleation of α-Fe through increasing the number-density of nucleation sites in as-quenched Fe_87−xZr_3.5Nb_3.5B₆Cu_x ribbons. However, at high Cu dopants (x≥3.5) the nucleation effect of α-Fe becomes weak, possibly connected with the reduction of effective number-density of Cu clusters due to the coarsening effect of them. Among as-quenched Fe_87−xZr_3.5Nb_3.5B₆Cu_x ribbons prepared with a wheel speed of 35 m/s, the as-quenched Fe₈₄Zr_3.5Nb_3.5B₆Cu₃ (x=3) ribbon with the largest permeability (2.4×10⁴ at 1 kHz) and saturation magnetic induction (1.18 T), possibly has the highest number-density of Cu clusters which can serve as nucleation sites for α-Fe grains.