Obtention of anisotropic barium hexaferrite from a siderurgical waste

Abstract

We report the production of anisotropic permanent magnets of barium hexaferrite using rolling scale (siderurgical waste) as starting material. A facility was designed and constructed and further tested for the industrial production of the anisotropic permanent magnets. The characteristics of both the ferrite powder and the compacts resulting of pressuring and sintering processes are described. In different stages parameters as grinding time and temperature were controlled. The samples were structurally and magnetically characterized. X-ray diffraction and Mössbauer spectroscopy were used for phase identification, while scanning electron microscopy allowed the determination of the average grain size. The magnetic behavior was also measured. This work proves that the ferric oxide produced from rolling scale of the national siderurgical industry can be used to obtain anisotropic material. Initial technological parameters of the process are proposed.