CRYSTAL ORIENTED MANGANESE ZINC FERRITES MADE FROM ACICULAR FINE PARTICLES

The acicular Mn-Zn ferrite fine particles composed of 65.6 mol% Fr, 21 .9 mol% Mn and 12.5 mol% Zn were made. These Mn-Zn ferrite particles w ere etched in 1N-HCl solution for 3hrs. Tile fine particle was made up of several crystallites whose long axis were 0.2-1.0 mu m, and arrang ed to [311] direction. These fine particles were pressed with applying magnetic field. The oriented Mn-Zn ferrites were prepared by sinterin g at 1250 degrees C for 4hrs in air and then cooling in nitrogen atmos phere. The oriented Mn-Zn ferrite exhibited strong crystal orientation similar to the single crystal of it. The magnetic anisotropy constant s were K-1=2.5 x 10(3) erg/cc and K-2=-0.2 x 10(3) erg/cc and the easy magnetization axis was [100] direction.