Influence of Ca substitution on the microstructure and magnetic properties of SrLaCo ferrite

Abstract M-type ferrites Sr (0.55− x ) Ca x La 0.45 Fe 11.65 Co 0.35 O 19 ( x =0, 0.05, 0.15, 0.25 and 0.35) were prepared by the ceramic process. Phase composition, morphology and sublattice occupation of the material were characterized by X-ray diffraction, scanning electron microscopy and Mossbauer spectroscopy, respectively. Magnetic properties of the materials were tested by a vibrating sample magnetometer. The results show that the samples are all composed of single M-type hexagonal ferrite after the Ca substitution, while the lattice constant c decreases and the lattice constant a does not change basically with increase of the substitution amount. In addition, the intrinsic coercive force increases obviously when the Ca substitution amount x 3+ sublattice occupations suggested by Mossbauer spectroscopy.