| Popis: |
Nanostructured Fe1−xSix (x=0.05, 0.1, 0.15 and 0.2) powders are prepared by different multi-step milling and annealing treatments. The microstructure and magnetic properties are investigated for all alloys. The minimum crystallite size of as-annealed powders (∼40 nm) is found to be larger than in as-milled ones (∼15 nm). It is found that microstrains of 2- and 4-step processes are close to those of the as-received powders. The lattice parameter decreased ∼0.5% and 0.9% for the powders that experienced milling and annealing at the last step, respectively. The Fe80Si20 powders prepared by 1- and 4-step treatments show the maximum (40–125 Oe) and minimum (20–26 Oe) coercivity, respectively. With increase in milling time, mass magnetization increased for all processes. This can be ascribed to diminution in magneto-crystalline anisotropy due to grain refinement. The maximum mass magnetization (160–199 Am2/kg) is achieved for the 4-step process. |
Full Text from ScienceDirect