Molten Salt Synthesis and Magnetic Properties of BaFe_(12)O_(19) Hexaferrite

Barium ferrite BaFe12O19(BaM) powders were prepared by using molten salt method.The preparation conditions of samples were investigated in detail,such as annealing temperature,soaking time,molten salt additive amount and Fe3+/Ba2+ molar ratios.The phase composition,microstructure and magnetic properties of the resultant powders were measured respectively by X-Ray Diffractometer(XRD),Scanning Electron Microscope(SEM) and Vi-brating Sample Magnetometer(VSM).Formation of BaM started below 750℃ in 0.5NaCl+0.5KCl.Single phase BaM powders were obtained while the Fe3+/Ba2+ molar ratios was controlled in the range from 10 to 11.5.The SEM results showed that the grains were regular hexagonal platelets when molten salt additive amount R was controlled in the range from 1 to 3.The resultant powders achieved under condition of Fe3+/Ba2+ molar ratios of 11.5 and cal-cination temperature of 1000℃ showed the saturation magnetization up to 71.9A.m2/kg,which was quite close to the theoretical value of 72A.m2/kg.