A mixture of Ho2O3 and Fe2O3 were mechanically alloyed followed by subsequent annealing to produce a single nanocrystalline HoFe2O4 phase. XRD patterns and magnetisation hysteresis curves were obtained for both the as-milled and annealed samples. XRD analysis indicates the formation of an initial amorphous phase in the as-milled powder. After annealing up to 1200°C, the material crystallises into nanosized (75 nm) monoferrite HoFe2O4 phase, accompanied by dramatic increment of magnetic properties. Moreover, the HoFe2O4 shows a ferromagnetic behaviour and a large hysteresis loop with Ms ≈ 72 emu/g, Hc ≈ 1.4 kOe and Mr ≈ 39 emu/g.
- Inderscience Publishers
- Structure and magnetic properties of nano-sized HoFe2O4 material
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