Nickel‐Zinc Ferrites: II, Preparation and Properties of Stoichiometric 32NiO/68ZnO Ferrite*

A nickel-zinc ferrite (43NiO/57ZnO) with 0.1 mol% cobalt ferrite was previously shown (1) to be very sensitive to Fe2O3 content, (2) to exhibit a maximum in resistivity and in μ0Q at a unique composition, and (3) to be stoichiometric at this composition in that the sum of the mol fractions of the divalent oxides equaled the mol fraction of Fe2O3. To determine (1) if these results are unique for the NiO/ZnO ratio 43/57 and (2) if Co is responsible for the high resistivity at the maximum, Co-free 32NiO/68ZnO ferrite was investigated. The results were similar to the previous ones, except that the unique composition is stoichiometric with respect not only to the metallic ions but also to oxygen.