抄録
Recently high coercivity ferrite magnets have been demanded for stators or rotors of motors and generators.
We took up the anisotropic strontium ferrite magnets pressed in wet for above request and studies the influence of the addition of some oxides such as SiO2, K2O, Li2O, MgO, BaO and Bi2O3 on the magnetic properties.
Addition of SiO2 delays the sintering reaction and decreases the degree of orientation at each sintering temperature below 1300°C.
Remanence Br and maximum energy product (BH)max decrease slightly with increase of SiO2, but coercive force BHC rises excellently. For instance, at 0.25∼0.6wt% SiO2, BHC more than 3, 000Oe was obtained with Br 3, 900∼4, 000G and (BH)max 3.3∼3.7 MGOe.
Duplex addition of SiO2 and K2O increases BHC and duplex addition of SiO2 and BaO increases Br and (BH)max respectively.
