SENNTIX-type amorphous alloys with high Bs and improved corrosion resistance

The magnetic, mechanical and corrosion properties were investigated for the SENNTIX-type Fe84−xB8.5Si4.5P3(Nb0.67Cr0.33)x alloys. The alloys show high saturation magnetization up to 1.53 T, low coercivity of 2.8-3.9 A/m and high effective permeability 11100-12900. In addition, the ribbons show good bending ductility even in the annealed state. By simultaneous addition of Cr and Nb to Fe-B-P-Si alloy, the corrosion potential increases nobler to the passive state. The corrosion resistance has been significantly improved compared with the (Cr, Nb)-free alloys, which is presumably due to the formation of (Cr, Nb)-rich passive film.