Crystal Structure and Magnetic Properties of X-type Hexagonal Ferrite Ba₂Ni₂Fe₂₈O₄₆

Abstract

Ba₂Ni₂Fe₂₈O₄₆ (Ni₂X) samples were prepared by using a conventional ceramic method. The crystal structure and magnetic properties of the samples were investigated. The X-ray diffraction patterns of the samples sintered at 1250°C and 1300°C were in agreement with the diffraction pattern simulated from the real space coordinates of Ba, Fe and O ions.
The Curie temperature was found to be 478°C, which was different from the Curie temperatures of M-type and Ni₂W-type hexaferrites. The single phase of X-type hexaferrite was obtained at 1250°C, which suggests that the sintering processes should be carefully controlled for the synthesis of the X-type hexaferrite.
The saturation magnetization of Ni₂X-type hexaferrite was higher than that of M-type and W-type hexaferrite at room temperature. Whereas, the coercivity was lower than that of M-type hexaferrite.