Textured Sc-Doped Barium–Ferrite Compacts for Microwave Applications Below 20 GHz

Sc is substituted for Fe in Ba M-type hexaferrite to reduce the anisotropy field and shift the ferromagnetic resonance (FMR) frequency to below 20 GHz. We have produced pure phase BaFe₁1ScO₁9powders having a platelet microstructure. These materials are pressed under an applied magnetic field of 95.5$times$10⁵A/m. Resulting compacts are sintered and are shown to have a clear uniaxial anisotropy with thec-axis perpendicular to the surface plane. Hysteresis loops display a squareness of 0.83 with a coercivity of$sim $186 kA/m. TheX-band FMR power derivative linewidth is measured to be 79.6 kA/m.