Influence of Co on microstructure and coercivity of (Ni0.5Fe0.5)80B10Si2Cu1Zr7 alloy

摘要

The effects of Co on microstructure, crystallization behavior and magnetic properties of (Ni0.5Fe0.5-xCox)(80)B10Si2Cu1Zr7 (x = 0 similar to 0.5) alloys were investigated. The results show that, the as-spun alloys remain lower coercivity (H-c) values (5 A/m similar to 14 A/m) over the whole Co content range, owing to their amorphous structure. After being annealed for 20 min above the onset temperatures of primary crystallization (T-x1), amorphous and nanocrystallines are coexisted in the alloys, and the crystal structure of nanocrystallines changes between fcc-(Ni, Fe, Co) and bcc-(Fe, Ni, Co) with the increasing Co content. In particular, it was found that H-c of the annealed alloys changes anomalously between 40 A/m and 1529 A/m with the increasing Co content, owing to the integrated action of grain size (D), magnetocrystalline anisotropy (K-1) and lattice distortion. Especially for the alloys with x = 0.2 and x = 0.3, serious lattice distortion is the dominant factor for their higher H-c value than 1000 A/m.

关键词