Abstract: A ferromagnetic amorphous alloy ribbon includes an alloy having a composition represented by FeaSibBcCd where 80.5?a?83 at. %, 0.5?b?6 at. %, 12?c?16.5 at. %, 0.01?d?1 at. % with a+b+c+d=100 and incidental impurities, the defect length along a direction of the ribbon's length being between 5 mm and 200 mm, the defect depth being less than 0.4×t ?m and the defect occurrence frequency being less than 0.05×w times within 1.5 m of ribbon length, where t and w are ribbon thickness and ribbon width, respectively, and the ribbon in its annealed state and straight strip form of the ribbon, has a saturation magnetic induction exceeding 1.60 T, and exhibits a magnetic core loss of less than 0.14 W/kg when measured at 60 Hz and at 1.3 T induction level. The ribbon is suitable for use in transformer cores, rotational machines, electrical chokes, magnetic sensors and pulse power devices.

Abstract: A ferromagnetic amorphous alloy ribbon includes an alloy having a composition represented by FeaSibBcCd where 80.5?a?83 at. %, 0.5?b?6 at. %, 12?c?16.5 at. %, 0.01?d?1 at. % with a+b+c+d=100 and incidental impurities, the ribbon being cast from a molten state of the alloy with a molten alloy surface tension of greater than or equal to 1.1 N/m on a chill body surface; the ribbon having a ribbon length, a ribbon thickness, and a ribbon surface facing the chill body surface; the ribbon having ribbon surface protrusions being formed on the ribbon surface facing the chill body surface; the ribbon surface protrusions being measured in terms of a protrusion height and a number of protrusions; the protrusion height exceeding 3 ?m and less than four times the ribbon thickness, and the number of protrusions being less than 10 within 1.5 m of the cast ribbon length; and the alloy ribbon in its annealed straight strip form having a saturation magnetic induction exceeding 1.

Abstract: A ferromagnetic amorphous alloy ribbon includes an alloy having a composition represented by FeaSibBcCd where 80.5?a?83 at. %, 0.5?b?6 at. %, 12?c?16.5 at. %, 0.01?d?1 at. % with a+b+c+d=100 and incidental impurities, the ribbon being cast from a molten state of the alloy with a molten alloy surface tension of greater than or equal to 1.1 N/m on a chill body surface; the ribbon having a ribbon length, a ribbon thickness, and a ribbon surface facing the chill body surface; the ribbon having ribbon surface protrusions being formed on the ribbon surface facing the chill body surface; the ribbon surface protrusions being measured in terms of a protrusion height and a number of protrusions; the protrusion height exceeding 3 ?m and less than four times the ribbon thickness, and the number of protrusions being less than 10 within 1.5 m of the cast ribbon length; and the alloy ribbon in its annealed straight strip form having a saturation magnetic induction exceeding 1.

Abstract: A ferromagnetic amorphous alloy ribbon includes an alloy having a composition represented by FeaSibBcCd where 80.5?a?83 at. %, 0.5?b?6 at. %, 12?c?16.5 at. %, 0.01?d?1 at. % with a+b+c+d=100 and incidental impurities, the defect length along a direction of the ribbon's length being between 5 mm and 200 mm, the defect depth being less than 0.4×t ?m and the defect occurrence frequency being less than 0.05×w times within 1.5 m of ribbon length, where t and w are ribbon thickness and ribbon width, respectively, and the ribbon in its annealed state and straight strip form of the ribbon, has a saturation magnetic induction exceeding 1.60 T, and exhibits a magnetic core loss of less than 0.14 W/kg when measured at 60 Hz and at 1.3 T induction level. The ribbon is suitable for use in transformer cores, rotational machines, electrical chokes, magnetic sensors and pulse power devices.