On synthesis of Ba[Fe.sub.12][O.sub.19], Sr[Fe.sub.12][O.sub.19], and Pb[Fe.sub.12][O.sub.19] hexagonal ferrite ceramics with multiferroid properties

We analyze the possibility of obtaining M-type hexagonal ferrites of barium, strontium, and lead with multiferroid properties with the help of ceramic technology. Using the modified ceramic technology (especially pure initial raw materials, admixture of [B.sub.2][O.sub.3], and sintering in the oxygen atmosphere), we obtained for the first time the Ba[Fe.sub.12][O.sub.19] and Sr[Fe.sub.12][O.sub.19] samples with intense multiferroid properties at room temperature. At the same time, the employed technology does not make it possible to obtain Pb[Fe.sub.12][O.sub.19] samples exhibiting ferroelectricity. The multiferroid characteristics of experimental samples are compared with the characteristics of classical high-temperature multiferroic BiFe[O.sub.3] and with the characteristics of Ba[Fe.sub.12][O.sub.19], Sr[Fe.sub.12][O.sub.19], and Pb[Fe.sub.12][O.sub.19] ferrite ceramics obtained in accordance with polymer precursor technology. We propose a mechanism explaining multiferroid properties of the hexagonal ferrite ceramic samples and note the importance of our results for applications. DOI: 10.1134/S1063784215080150