PERMANENT-MAGNET MATERIALS AND THEIR MANUFACTURING PROCESSES Russian patent published in 1998 - IPC

FIELD: R-Fe-B alloy base materials for permanent magnets and their manufacture. SUBSTANCE: R means at least one of rare- earth elements including yttrium. Material has in its composition, atom percent: R - 12-16; boron - 4-8; oxygen - 0.08-2.1; iron - the rest; it uses R₂Fe₁₄B as main phase in the amount of more than 90 volume percent with grain size maximum 10 mcm, degree of orientation 85% at loose material density minimum 7.45 g/cm³ and A+B sum minimum 59, where A is assumed as (BH)_max and B, as the value of iH_c.. Square-law characteristic (Br²/4)/(BH)_max equals 1.01-1.045. Manufacturing process includes strip casting to produce workpiece, crushing the latter by hydrogenation, dehydrogenation, followed by pulverizing in inert gas to 1-10 mcm degree of fineness, orienting magnetic field by means of pulse, compressing, and agglomerating. EFFECT: improved quality of material obtained; facilitated procedure. 100 cl, 2 dwg , 8 tbl