Chaocheng Liu

Influence of heat treatment temperatures on microstructure and characterization of BaFe22+Fe15.63+O26.4 hexaferrite

A series of W-type hexagonal ferrites with composition BaFe22+Fe15.63+O26.4 at different temperatures was synthesized via a ceramic process in a reducing atmosphere during the whole process of calcination and sintering. The phase identification of magnetic powders was performed by X-ray diffraction. The result of XRD confirmed the appearance of a pure phase hexagonal crystal structure with temperature from 1290 to 1330 °C. The microstructures of the magnets were investigated by using a HS-4800 scanning electron microscopy. The magnetic properties of the magnets were measured by a permanent magnetic measurement equipment. B–H curves show that the magnetic properties such as remanence, magnetic induction coercivity, intrinsic coercivity, saturation magnetization and maximum energy product are significantly affected by calcination and sintering temperatures. The optimized sintering and calcination temperatures are 1280 and 1300 °C, respectively.