INVESTIGATION OF THE FORMATION MECHANISM OF HEXAGONAL FERRITES IN THEBAO - COO - FE2O3 SYSTEM

The formation of W S, Y, Z and U cobalt hexaferrites, which are also t ernary compounds in the BaO-CoO-Fe2O3 system, was studied. The samples were studied in nonisothermal conditions (DTA) and in isothermal cond itions by thermal treatment at 1200, 1300 degrees C, during 2-20 hours . The phase composition and also the network parameters a and c of the hexaferrite in the resulted samples were established bg using X-ray d iffraction method. The main intermediate phases evidenced during forma tion of the studied compounds are barium hexaferrite and barium monofe rrite. In the experimental conditions ,used in our work, the formation of W, Y, Z and U cobalt hexaferrites was established. It was also obs erved that, instead of compound X, a solid solution between W and bari um hexaferrite with the structure of the compound W was formed.