抄録
Fine powders of Mn-Zn Ferrite were manufactured by the co-precipitation method and sintered into disks.
The effects of pH and temperature in the co-precipitation and aging upon the properties of the sintered ferrites were investigated. As a measure of sintering, the initial permeability and the density were adopted. The pH was found to have a remarkable effect.
The most favorable pH value, giving the maximum initial permeability and density, lies between 9.3 and 13.
The degradation in the lower pH range may be ascribed to the ultra-fineness and included water in the powders. On the other hand, the decrease in the permeability in the upper range proved to be caused by residual Na in the ferrite.
The above-mentioned feature varies with the aging temperature. The degradation in the lower pH range were enhanced at 20°C and that in upper pH at 90°C.