Synthesis and Multiferroic Properties of M-type SrFe12O19 Hexaferrite Ceramics

SrFe 12 O 19 samples exhibiting intense multiferroic properties at room temperature are for the first time prepared using a modified ceramic technology (maximum polarization of P max = 43.0–45.5 μC/cm 2 , residual polarization of P r = 22.5–24.5 μC/cm2, and an electric coercive field of E c = 210–216 kV/m). The ferroelectric properties of the samples are obtained thanks to modification of the surface of grains. During ferritization and sintering, the grains are enveloped with a thin B 2 O 3 dielectric film, which leads to a decrease in the electrical conductivity between grains and a significant increase in the resistivity of the ceramic. A mechanism to explain multiferroic properties is proposed; the practical significance of the results is noted.