Morphology and magnetic properties of SrFe 12 O 19 synthesized with oxidized scale

Abstract A series of Strontium hexaferrite (SrFe 12 O 19 ) were successfully synthesized at 1100 °C for 2 h by the molten-salt synthesis method using SrCO 3 and oxidized scale as raw materials. The characteristics morphology and magnetic properties of as-prepared SrFe 12 O 19 powders in different eutectic molten salt mixtures were discussed. The morphology feature has an important influence on magnetic properties of SrFe 12 O 19 , in particular of the coercivity. Because the basal plane of M-type strontium hexaferrite is easily magnetized, the obtained samples of platelet-shaped with large ratio of width to thickness in KCl–Na 2 SO 4 and KCl–K 2 SO 4 molten salts display a low coercivity which is 2862 Oe and 2687 Oe, respectively. The H c , M s , M r and (BH) max of the obtained SrFe 12 O 19 with irregular elliptical shape in NaCl–KCl molten salt are 4043 Oe, 60.77 emu/g, 33.75 emu/g, 0.61 MG Oe. The multi-domain structure of all samples may cause the coercivity lower than the theoretical value.