Effect of Y-La-Co substitution on microstructure and magnetic properties of M-type strontium hexagonal ferrites prepared by ceramic method

Highlights: • Y-La-Co doped strontium hexagonal ferrites have been prepared by ceramic process. • Effects of Y-La-Co doping on the microstructure and magnetic properties were revealed. • Lattice constants, chemical bond and atom occupancy were studied for the samples. • The coercivity (H_c) showing an increasing trend due to the increasing doping content. • This study can provide an important reference for research and application in novel magnetic fields. M-type permanent magnetic ferrites Sr_0.95−xY_0.05La_xFe_11.75Co_0.25O₁₉ (x = 0.00, 0.10, 0.20, 0.30, 0.40) have been prepared by ceramic process and investigated systematically. The phase compositions were examined by X-ray diffraction, the results showed that the single phase was obtained when x ≤ 0.30. The morphology of the magnets was investigated by scanning electron microscopy (SEM), the micro-morphology of the particles exhibited the uniform plane hexagonal structure with different lanthanum content. Magnetic properties of the sample were measured by a physical property measurement system-vibrating sample magnetometer (PPMS-VSM). The saturation magnetization (M_s) decreases constantly with the increasing of La content (x). However, the coercivity (H_c) increases as the increasing of doping content.