Amorphous FeNiCoCuSiBCr Alloys with Superior Direct Current Tolerant Characteristics

Amorphous Fe62-x Ni19Cox Cu0.1 Si3.8 B14 Cr1.1 (x = 0, 1, 5, 10) ribbons were annealed under magnetic field and tensile stress, respectively, and their magnetic properties were investigated. Fe73.5 Cu1 Nb3 Si15.5 B7 and Fe66 Ni10-Cu1 Nb3 Si11 B9 nanocrystalline alloy ribbons were also fabricated for comparison. Excellent DC tolerant property was obtained in the amorphous FeNiCoCuSiBCr ribbons after thermomagnetic treatment and the constant permeable property was improved with increasing Co content. The relative permeability was constant up to the DC bias field of approximately 6 × 10−4, 9 × 10−4, and 10 × 10−4 T and the values of relative permeability μr were 1650, 1200, and 1000 with the Co content being 0, 5 at. %, and 10 at. %, respectively. Besides, stress-annealed FeNiCoCuSiBCr alloy ribbons were proved to exhibit positive saturation magnetostriction constant λs.