Magnetic properties of Sr-Zn system W-type hexagonal ferrite magnets prepared by new manufacturing method

Sr-Zn system W-type hexagonal ferrite magnets were prepared by a novel manufacturing method of SrO addition after semisintering treatment, and without atmosphere control. It was found that this process was very useful in stabilizing the W-type hexagonal structure. The optimum condition of making magnets and some properties of typical specimens are as follows: the chemical analysis composition is Sr/sup 2+/ /sub 1.248/Zn/sup 2+/ /sub 2.655/Fe/sup 2+/ /sub 0.625/Fe/sup 3+/ /sub 14.981/O/sub 27/ the semisintering condition is 1275 degrees C*0.5 h in air; and the magnetic and physical properties are J/sub m/=0.350 T, J/sub r/=0.323 T, H/sub cJ/=96.6 kA/m, H/sub cB/=94.4 kA/m, (BH)/sub max/=17.0 kJ/m/sup 3/, T/sub C/=349 degrees C, H/sub A/=988 kA/m, K/sub A/=1.72*10/sup 5/ J/m/sup 3/, and n/sub B/=34.5 mu /sub B/.<
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