抄録
The effects of CaO and SiO2 inter-additives on magnetic and physical properties of Ca-La-Co system ferrite sintered magnets were discussed. The results show that the maximum magnetization and remanence of the sintered magnets decrease with an increase in the ratio of SiO2 to CaO inter-additives, because non-magnetic materials α-Fe2O3 are formed with an increase in the ratio. On the other hand, the coercivity HcJ of Ca-La-Co system sintered magnets increase with an increase in the SiO2 additives, because the average particle size of sintered magnets becomes smaller. Whereas, HcJ of Ca-La-Co system sintered magnets decrease with an increase in the CaO inter-addition because the crystal growth of the sintered magnets occurred due to CaO inter-additive. Optimum magnetic properties and conditions in this experiment were as follows; inter-additives: 0.3 wt.% SiO2 and 0.5 wt.% CaO, sintering temperature: 1200°C, Br=0.429 [T], HcJ=278 [kA/m], (BH)max=34.5 [kJ/m3].
