抄録
An experiment was carried out to investigate the manufacturing condition for chemical coprecipitation method, and the effect of Li2O3 substitution on the magnetic and physical properties of Co-Ni spinel ferrite fine particles. As one of the examinations, alkaline aqueous solution inflowed into the metal mixture solution on a constant speed. As a result, this method yeilded fine particles with more stable properties than the pH control method (the conventional method). As regards the (CoO)0.5(NiO)0.5-x(Li2O3)0.5x·Fe2O3 (x = 0—0.5) composition, the new method showed a good properties in (CoO)0.5(NiO)0.3(Li2O3)0.1·Fe2O3 composition, with magnetic properties of σs = 64.3 x 10-6 Wb·m/kg (51.2 emu/g), HcJ = 406.0 kA/m (5.12 kOe). K1 = 10.0 x 104 J/m3, K2 = -39.6 x 104 J/m3. The average particle size was about 34 nm. The rotational hysteresis integral (Rh), which was related to the magnetization mechanism of these fine particles was 1.66, and it was found that the magnetization mechanism was an incoherent rotation one.
