Size controlled preparation of Fe-B-P submicrometre particles and magnetic performance

摘要

Fe-B-P submicrometre particles were synthesised by a novel chemical method. The size of the Fe-B-P particles (0.1-1 mm) is easily controlled by tuning the NaBH4 concentration and its dropping speed. The saturation magnetisation (M-s) of Fe-B-P submicrometre particles is >130 emu g(-1), whereas the coercivity is <10 Oe. The permeability of the composites made of Fe-B-P particles (similar to 0.3 mu m) and NiZn ferrite nanoparticles (10 nm) is similar to 25 when the volume percentage of NiZn ferrite is 30-50%. The resonance frequencies are all similar to 1 GHz for pure Fe-B-P particles and the composites.