Abstract
In this study, the glass-forming range, microstructural and soft magnetic properties of (Fe1?x-yCoxNiy)86B14 alloys were investigated in the as-cast state and after ultra-rapid annealing. The glass-forming range is seen to be the greatest for Fe-rich compositions and is limited to x ≤ 0.8 and y ≤ 0.3. Within the glass-forming range, this alloy system is observed to contain nano-scale grains with bcc and fcc structures after ultra-rapid annealing and a clear bcc-fcc transition is seen for Ni-rich compositions. Both the coercivity (Hc) and saturation magnetic polarization (Js) for the nanocrystalline (Fe1?x-yCoxNiy)86B14 alloys are generally increased by Co addition and reduced by Ni addition. Js is confirmed to be the largest for (Fe0.8Co0.2)86B14 at 1.88 T in the as-cast state and 1.98 T for (Fe0.7Co0.3)86B14 in the nanocrystalline state. The minimum Hc of 2.0 A/m is obtained for nanocrystalline (Fe0.80Co0.05Ni0.15)86B14 with a Js of 1.71 T. This composition also exhibits a lower core loss compared to the nanocrystalline Fe86B14 and Fe-based amorphous alloys at frequencies up to 1 kHz.
NSTL
Elsevier