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Ultrafine particles were produced by evaporating Fe 90 B 10 in Ar or N 2 atmosphere and Fe 2%Si in N 2 atmosphere(at 133 3 Pa Pressure ) respectively. The phases,sizes,morphologies, magnetism and iron contents of the ultrafine particles were investigated and analyzed by means of transmission electron microscope (TEM),X ray diffraction (XRD) and vibrating samples magnetometer (VSM) at room temperature and chemical titration.The particles prepared from Fe 90 B 10 in Ar and taking the size of 6 nm,are poor crystal.The particles prepared in N 2 taking the size of 8 nm are non crystal. The morphology of the Fe B particles is identically spherical shape.The size of Fe Si particles, whose contents are main α Fe and a few Fe 3Si,is about 20 nm.The magnetic measurement shows that all of the three kinds of particles are ferromagnetic,but the specific saturation magnetization and the maximum coercivity H c at room temperature are very different from iron contents.So the properties of the particles produced from same Fe based material but in different atmosphere (Ar or N 2) are different from that of particles produced from different Fe based material but in same N 2 atmosphere.It may be connected with the activity of melting iron before evaporating out.
The phases, sizes, morphologies, magnetism and iron contents of the ultrafine particles were investigated and analyzed by means of transmission electron microscope (TEM), X-ray diffraction (XRD) and vibrating samples magnetometer (VSM) at room temperature and chemical titration. The particles prepared from Fe 90 B 10 in Ar and taking the size of 6 nm , are poor crystal. These particles prepared in N 2 taking the size of 8 nm are non crystal. The morphology of the Fe B particles is identically spherical shape. The size of Fe Si particles, whose contents are main α Fe and a few Fe 3Si, is about 20 nm. The magnetic measurement shows that all of the three kinds of particles are ferromagnetic, but the specific saturation magnetization and the maximum coercivity H c at room temperature are very different from iron cont ents.So the properties of the particles produced from same Fe based material but in different atmosphere (Ar or N2) are different from that of particles produced from different Fe based material but in same N2 atmosphere. It may be connected with the activity of melting iron before evaporating out.