Fe3O4 Formation by Ball Milling of Fe2O3 Powder

The influence of mechanical milling of a hematite powders on formation of magnetite was studied by X-ray diffraction and thermal analyses and laser diffraction. In this work, the Retsch Emax planetary ball mill was used for mechanical milling of the hematite powders. According to X-ray diffraction data, the formation of a magnetite phase as a result of the mechanical activation of hematite powder within 30 min was established. The formation of 100% phase magnetite occurs with an increase in the time of mechanical milling up to 60 min. The results of X-ray diffraction analysis are well correlate with the data from thermal analysis. According to laser diffraction analysis the magnetite powders are large agglomerates consisting of nano-sized particles. An increase in the mass of milled hematite powder was shown by thermal analysis. It is associated with the oxidation process of magnetite to hematite as the result of heating in a furnace of analyzer furnace. This process starts at temperature of 150°C and continues 670°C. The formation of magnetite was confirmed by studies of the milled powders using thermal analysis and magnetization measurements.