Magnetic properties of substituted barium ferrite powders

Hexagonal barium ferrites were prepared using the citrate method. Cobalt and titanium were added in the amounts x from 0.2 to 1.1 ion /f.u. related to the formula BaCo/sub x/Ti/sub x/Fe/sub 12-2x/O/sub 19/. The heat treatment has been applied in three steps of 550/spl deg/C/5 hrs, 850/spl deg/C/2 hrs and 1100/spl deg/C/2 hrs. The following magnetic properties have been achieved: H/sub c//spl sim/80 kA/m, J/sub s/-120/spl times/10/sup -6/Tkg/sup -1/m/sup 3/, and J/sub r/-60/spl times/10/sup -6/ Tkg/sup -1/m/sup 3/ in the composition for which x is equal to 0.5 ion/f.u. The magnetic parameters have been measured by the vibration magnetometer.<
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