  We report an experimental study of the bimagnetic nanocomposites
CoFe2/CoFe2O4.The precursor material, CoFe2O4 was prepared using the
conventional stoichiometric combustion method. The nanocomposite CoFe2/CoFe2O4
was obtained by total reduction of CoFe2O4 using a thermal treatment at 350oC
in H2 atmospheres following a partial oxidation in O2 atmospheres at 380oC
during 120; 30; 15, 10, and 5 min. The X-ray diffraction and Mossbauer
spectroscopy confirmed the formation the material CoFe2/CoFe2O4 The magnetic
hysteresis with different saturation magnetization confirms the formation of
the CoFe2/CoFe2O4 with different content of CoFe2O4. The high energy milling to
the precursor material increase the coercivity from 1.0 to 3.3 kOe, however the
same effect was not observed to the CoFe2/CoFe2O4 material.
