Microstructure and Magnetic Properties of Textured Barium W-Type Hexaferrite with Rare-Earth La3+ Substitution

Abstract

Abstract Textured M-type barium hexaferrites (BaM) in form of BaLaxNi2Fe16-xO27 (x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5) were synthesized using a ceramic process. The effect of La3+ substitution on the microstructure and magnetic properties of the resulting BaW samples was investigated. Pure BaW phase formation for all samples was confirmed by the X-ray diffraction patterns. The scanning electron microscopy images revealed that the grains in the textured BaW had realigned along the hexagonal crystallographic c-axis, which was in good agreement with the results of magnetic hysteresis loops. Moreover, textured BaW with a high squareness ratio (Mr/Ms= 0.80) was obtained. Due to the La3+ substitution, the magnetocrystalline anisotropy field (HA) decreased dramatically while maintaining the c-axis anisotropy. The textured BaW are potential candidates for the design of self-biased microwave devices such as circulators and isolators operated at Ku or X band.