Glass-coated Co-rich amorphous microwires with enhanced permeability

Abstract Nearly-zero magnetostriction glass-coated amorphous (Co 1− x Mn x ) 75 Si 10 B 15 ( x =0.06, 0.07 and 0.08 at.%) microwires have been fabricated by Taylor-Ulitovsky technique. Such slight changes in x resulted in rather strong changes in the hysteresis loops. The optimum soft magnetic characteristics in as-cast material are observed for x =0.07. The effect of heat treatment and chemical etching has been investigated in order to further improve their magnetic properties. Magnetic field annealing at elevated temperature and/or long-time chemical etching results finally in magnetic bistability of microwires. Experimental results are interpreted in terms of the balance between magnetoelastic anisotropy arising from internal stresses, the shape anisotropy and the induced anisotropy by field annealing. Obtained experimental results can be used for tailoring high initial permeability of soft magnetic materials with enhanced initial permeability.