Structure and magnetic properties of Co-rich nanocrystalline soft magnetic alloys with low coercivity

Abstract

In this study, a series of five nanocrystalline soft magnetic alloys, with compositions equally spaced between (Co0.70Fe0.20Ni0.10)88Zr7B4Cu1 and (Co0.90Fe0.08N0.02)88Zr7B4Cu1, was fabricated by melt spinning and subsequent isothermal annealing. The alloys were annealed at 823 and 1023K for 3600s, and the resulting structure and magnetic properties are reported. X-ray diffraction indicates that 1h isothermal annealing at 823K results in body-centered cubic crystallites in the Fe∕Ni poor alloys and in a mixture of body-centered cubic and face-centered cubic crystallites in most Fe∕Ni rich alloy. The (Co0.90Fe0.08N0.02)88Zr7B4Cu1 alloy annealed at 823K has a low coercivity of 8A∕m and a relatively high saturation magnetization of 131.1Am2∕kg. The magnetic properties of these alloys are discussed in terms of their nanocrystalline microstructures.

Nanocrystalline soft magnetic ribbons with high relative strain at fracture

“…10,11 In previous studies by the present authors, the nanocrystallites were found to be ഛ10 nm in diameter for all compositions. 12,13 This suggests that the amorphous phase plays a prominent role in governing the mechanical behavior of the alloys presented in this work.…”