Ceramics-Silikáty 33, (2) 97 - 104 (1989)

A method was worked out for the preparation of dispersed powdered magnesium, calcium and zinc ferrites by precipitation in the medium of molten salts. The synthesis of compounds in melts, compared to the classical solid phase reaction and the preparation from a suitable precursor, has the advantage of allowing the size, and sometimes also the morphology of the crystals, to be controlled. However, the main advantage of molten salts as a reaction medium is based on its convenient thermodynamic and transport properties. The study was concerned with investigating the effect of temperature and time of heating on the dispersity and morphology of the ferrites in question. It was found that the synthesis can be effected at considerably lower temperatures than the direct synthesis from oxides, and the products show a high phase purity and a comparatively narrow log-normal particle size distribution of crystals with the mean size of less than 1 μm.