A Study of Amorphous Alloy Cutting Core

The large magnetostriction of iron-base amorphous alloys causes deterioration in magnetic properties during annealing, cutting, and other high-stress processing. The authors formed elliptical wound iron cores using Fe79B16Si5 film, annealed them in N2 gas at 450°C, and impregnated them in epoxy and silicon resins before hardening under various conditions. Measurements of the high-frequency iron loss and AC B-H characteristics indicated an increase in coercive force after impregnation, and a doubling of the iron loss between impregnation and cutting. The original iron loss could be restored by polishing.