Influence of the Tensile Stress on the Magnetostriction Resistivity and Magnetic Anisotropy of Co-Rich Metallic Glasses. TSRO and CSRO Correlation

Abstract

The influence of tensile stress on the magnetic properties of amorphous alloys is reviewed for (CoFeNi) SiB compositions.(i) The compositional and thermal dependence of magnetostriction is examined as well as its evolution during structural relaxation. The close relation between the observed changes in magnetostriction and electrical resistivity after thermal annealing is pointed out. These results strongly suggest the existence of well defined chemical short range order, CSRO.(ii) The more remarkable characteristics of the anelastic anisotropy induced by stress annealing in the (Co1-xFex)75Si15B10 system are summarised. The compositional dependence of anelastic anisotropy was found to be surprisingly identical to the compositional dependence of the resistivity changes. These results indicate that a maximum degree of CSRO can be reached for the composition rate Co/Fe = 3.(iii) It was recently shown that the magnetostriction constant of some low-magnetostrictive metallic glasses linearly decreases with the applied tensile stress. The typical decreasing rate, dλs/dσ, ranges from −6 to −1 × 10−10 (MPa)−1.The origin of this experimental evidence is discussed by taking into account its relation with the stress induced anisotropy. Some new results dealing with the influence of the tensile stress on the electrical resistivity are also reported.