On the saturation magnetostriction in low magnetostrictive Co-rich amorphous wires

Abstract

This paper presents some results concerning the saturation magnetostriction ( λ s) in low magnetostrictive Co-rich amorphous wires tested in the as-cast state and after annealing. The replacement of Co or Fe with small amounts of Cr and Ni in nearly zero magnetostrictive Co-rich alloys determines small positive or negative λ s values, while the stress current annealing changes its magnitude. The saturation magnetostriction has been determined by means of the small-angle magnetisation rotation method and has been evaluated as +0.39×10 −6 for Co 65.25Fe 4.5Si 12.25B 15Cr 2Ni 1 and −1.15×10 −6 for Co 68.15Fe 2.35Si 12.5B 15Cr 1Ni 1 amorphous wires in the as-cast state. An increase up to about 5 times and a decrease up to about 2 times of λ s was observed for Co 65.25Fe 4.5Si 12.25B 15Cr 2Ni 1 and Co 68.15Fe 2.35Si 12.5B 15Cr 1Ni 1 amorphous wire, respectively, after stress current annealing.