Growth, structural and magnetic characterization of Co- and Ni-substituted barium hexaferrite single crystals

Large single crystals with sizes of up to 15 mm of cobalt and nickel-substituted M-type barium hexaferrite BaFe12−xMxO19 (M = Ni, Co) were obtained from carbonate flux at temperatures as low as 1260 °C. The Co and Ni contents in the crystals can be controlled via the content in the flux, but is restricted to about x ⩽ 0.3. An increasing amount of the substitution results in a monotonous reduction of the Curie temperature, the saturation magnetization at room temperature and the coercive force.