METHOD AND DEVICE FOR MANUFACTURING ANISOTROPIC POLYCRYSTALLINE FERRITE MATERIAL Russian patent published in 2004 - IPC

FIELD: producing magnetic record media, nonreciprocal microwave devices, permanent magnets, and working media of magnetic coolers. SUBSTANCE: proposed method for manufacturing anisotropic polycrystalline ferrite material from powdered W-type barium of BaCo_2-xZn_xFe₁₆O₂₇, system, where x = 1.0 - 1.4, includes preparation of ferrite powder and magnetic treatment of powder placed in nonmagnetic mold and exposed to magnetic field varying with time and space. Prior to magnetic treatment powder is mixed up with liquid. This mixture is exposed to magnetic field in horizontal plane sequentially in two directions spaced 60 to 120 deg. apart. Both components of magnetic field are chosen as gradually increasing and gradually decreasing low-frequency pulse trains whose maximal intensity is between 100 and 400 kA/m. For final operation powder is compressed by applying pressure to stop motion of ferrite particles. Then briquette resulting from powder compression is molded. Device implementing this method is described. EFFECT: enhanced degree of magnetic texture (magnetic anisotropy) of material. 3 cl, 3 dwg