Hydrothermal Preparation of Manganese Zinc Ferrites

Abstract
The hydrothermal powder preparation route is suited for achieving a very homogeneous, nanocrystalline franklinite powder. Compared to the conventional presintering via mixed oxide processing the hydrothermal route has advantages because of simplification for the powder preparation and more homogeneity caused by wet processes. As a result a preferritized powder suspension was synthesized which can be used to obtain a granulate and pressing it to the desired core shapes. The microstructure of the sintered cores is very homogeneous and almost free of pores compared to the conventionally produced cores. Excellent magnetic properties can be achieved by sintering under considerably lower temperatures. The initial permeability resulting from sintering under the same conditions is for hydrothermal based cores app. 20 % higher.