Evolution of the Morphology and Magnetic Properties of Flaky FeSiAl/MFeO (M = Mn, Co, Ni, Cu, Zn) Composites.

Nanosized spinel ferrites MFeO (M = Mn, Co, Ni, Cu, Zn)-coated flaky FeSiAl alloy composites were synthesized successfully. Nano-ferrites preferentially grow into nanoplatelets due to induced or restricted growth on the flaky surface of FeSiAl. With annealing temperature increasing, the ferrites' nanosheets thicken gradually and then grow into irregular particles. The annealing temperature not only affects the nanosized morphology and coating but also the magnetic properties of flaky FeSiAl composites. The saturation magnetization of CuFeO- or NiFeO-coated FeSiAl is approximate 69 emu/g, where the value of MnFeO-, CoFeO- and ZnFeO-coated FeSiAl show a decreasing trend generally from 64 emu/g to 55.7 emu/g annealing at 800 °C, respectively. The saturation magnetization of flaky FeSiAl composites was improved with the increased annealing temperature, except for those coated with ZnFeO and NiFeO. These results are useful for improving the comprehensive properties of ferrite-coated flaky FeSiAl alloy composites.