Magnetization reversal and interactions in SrFe12O19

Coercivity and interactions in coprecipitated and ceramic SrFe12O19 (Sr-M) hexaferrite samples were studied using remanence curves and magnetic viscosity in addition to microstructural considerations by means of SEM analysis. Following a magnetic viscosity formalism, the activation volume was obtained and interactions were evaluated using the M technique. Even for a coprecipitated sample with a high coercive field (H-c=6100Oe), the experimental activation volume indicates a non-coherent mechanism for magnetization reversal and demagnetizing-like interactions were found in this isotropic sample with large aspect ratio particles; also demagnetizing-like interactions were found for a thermally treated coprecipitated sample and a ceramic sample.

Coercivity and interactions in coprecipitated and ceramic SrFe12O19 (Sr-M) hexaferrite samples were studied using remanence curves and magnetic viscosity in addition to microstructural considerations by means of SEM analysis. Following a magnetic viscosity formalism, the activation volume was obtained and interactions were evaluated using the DM technique. Even for a coprecipitated sample with a high coercive field (Hc 1/4 6100 Oe), the experimental activa- tion volume indicates a non-coherent mechanism for magnetization reversal and demagnetizing-like interactions were found in this isotropic sample with large aspect ratio particles; also demagnetizing-like interactions were found for a thermally treated coprecipitated sample and a ceramic sample.