The microstructure of γ-Fe2O3and its effects on the magnetization properties

Some doubts on the microstructural nature of γ-Fe2O3were recently raised. New experimental data on the magnetics, wide and low-angle X-ray scattering, and print-through for γ-Fe2O3are reported. It is proved that γ-Fe2O3is composed of a mosaic of "islands" whose size is much smaller than the size detectable on transmission electron microscopy (TEM) micrographs. This defective structure of the particles must, therefore, be taken into account in order to explain anomalies in print-through data for γ-Fe2O3tapes and their overall magnetization properties. The model for γ-Fe2O3particles which arises from this work induces a reconsideration of the magnetization reversal models for single-domain γ-Fe2O3particles.