Structural and magnetic properties of Sr1−xLaxFe12−x(Cu0.5Co0.5)xO19 hexaferrites prepared by the solid-state reaction method

Hexaferrite Sr1−xLaxFe12−x(Cu0.5Co0.5)xO19 (0 ≤ x ≤ 0.50) magnetic powders and magnets were synthesized by the solid-state reaction method. The phase compositions of magnetic powders were investigated by X-ray diffraction. The single magnetoplumbite phase is obtained in magnetic powders with x from 0 to 0.40. At x = 0.50, CoFe2O4, and α-Fe2O3 were observed. The morphology of the materials was characterized by a field-emission scanning electron microscopy. The particles were hexagonal platelets. Magnetic properties of the materials were measured by a permanent magnetic measure equipment. The remanence of the materials increases with x from 0 to 0.50. However, the intrinsic coercivity and magnetic induction coercivity of the materials increase with x from 0 to 0.15, and decreases when x varies from 0.15 to 0.50. Accordingly, the maximum energy product of the materials first increases with x from 0 to 0.35, and then decreases when x exceeds 0.35.