PROCESS FOR PRODUCING POWDER OF OXIDE HEXAGONAL FERROMAGNETIC WITH W-STRUCTURE Russian patent published in 2007 - IPC B22F9/16 H01F1/34 

FIELD: production of ferrite powders possibly used in radio engineering and radio electronics as radiation absorbing coatings and in magneto-pharmacology.

SUBSTANCE: process is realized at taking components in next relation, mass %: BaO₂, 11.45 - 11.72; Fe₂ O₃ , 57.8 -51.4; CoO, 3.5 - 3.63; ZnO, 7.16 -7.32; Fe - the balance. Said components are mixed by mechanically activating in energy intensity apparatus for 1 - 3 min at energy intensity factor 20 - 60 g and subjected to heat treatment by initiating burning process of exothermic mixture and sintered at temperature 1160 - 1180°C for 15 - 20 min. Such process allows produce oxide hexagonal ferromagnetic with content of W-phase 98%. Static magnetic properties of such powder exceed properties of known composition and its dynamic characteristics provide doubled working frequency band due to using coating of such powder as electromagnetic energy absorber. Investigation of main magnetic characteristics of product shows that it is possible to use coating of such material for effective absorption of radiation at operation in frequency range 6±1 GHz.

EFFECT: lowered number of operations of manufacturing cycle, shortened time period for performing process, stable magnetic characteristics of powder in wide temperature range.

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