Optimization of magnetic and structural properties of Sr ferrite prepared by low-temperature combustion

Abstract

Fine strontium hexaferrite particles were prepared by the low temperature auto-combustion method. Aqueous solution of the corresponding metal salts and a combustible co-reactant compound -glycine were used as initial precursor. The resulting powders were calcined at various temperatures from 750°C up to 1100°C. The microstructure and magnetic properties were investigated by the Mössbauer spectroscopy, thermomagnetic analysis, scanning electron microscopy, and vibrating magnetometer. The particles of sizes less than 1 μm have monophasic hexagonal structure. Coercivity Hc ≈ 400 kA/m, specific saturation polarization Js-m ≈ 72 × 10-6 Tm3 kg-1 and remanence polarization Js-r ≈ 43 × 10-6 T m3 kg-1 were achieved for the Sr ferrite annealed at 850°C for 6 h.