HEXAFERRITE PARTICLES PREPARED BY SOL-GEL TECHNIQUE

The chemical sol-gel route is used to prepare undoped and substituted barium and strontium ferrites. Beside standard crystallographic and ma gnetic measurements, ferromagnetic resonance experiments are used to a nalyze the formation of the hexaferrite phase and to determine the ani sotropy field strength. Specific saturation magnetization, coercive-an d anisotropy field strength are determined depending on the heat treat ment of the gel and the ion-ratio in the starting sol. The special pre paration conditions and the magnetic properties of sol-gel derived [Ba ,Sr]Me(x)(2+)Ti(x)(4+) Fe12-2xO19 with Me(2+)=Zn2+,Co2+ and x=0-1.0 ar e discussed. Additionally, the typical morphology of the investigated powders is underlined by REM- and TEM- photographs.