Influence of Mn addition on magnetic and structural properties of barium hexaferrite

Two-phase nano-powders based on Ba hexaferrite with addition of Mn have been obtained by a sol-gel auto-combustion method. Composition dependence of magnetic and structural properties has been studied using magnetic measurements, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The observed decrease of saturation magnetization and coercivity with increase of Mn content is mainly attributed to the presence of Fe oxide as a result of Ba depletion. SEM images show chemically homogeneous, non-regular shaped agglomerated nano-particles (50-200 nm).