MAGNETIC-PROPERTIES OF AS2O3-DOPED AND SB2O3-DOPED BA-M HEXAGONAL FERRITES PREPARED BY THE SOL-GEL METHOD

Abstract

Ba-M hexagonal ferrites with As2O3 and Sb2O3 doping have been prepared in the composition series BaO.(6- x)Fe2O3 .xM2O3 (M = As or Sb) with 0 less-than-or-equal-to x less-than-or-equal-to 0.4 by the sol-gel route. The precursor sol is prepared by using barium acetate and the chlorides of iron and arsenic/antimony respectively. Pelletized powders of these hexaferrites are sintered in the temperature range 1100-1500 K for a period extending to 3 h. The grain sizes in the samples range from 1 to 6 mum. The magnetization and coercivity change as a function of the dopant concentration of arsenic and antimony oxides. A cationic distribution scheme with As3+ and Sb3+ ions occupying the octahedral sites in the R block and the R-S boundary respectively of the Ba-M hexagonal crystal structure can explain the magnetization characteristics of these samples.