METHOD OF RECTIFYING METAL POWDER PRODUCTION Russian patent published in 2001 - IPC

FIELD: powder metallurgy; applicable in production of high-purity powders of tantalum and niobium with high specific surface for manufacture of capacitors. SUBSTANCE: method includes introduction of rectifying metal salts and halide of alkali metal and active additive to reactor made of nickel-containing material; melting of salts in presence of additive and reduction of rectifying metal with alkali metal in atmosphere of inert gas with stirring of melt. Active additive is used in the form of rectifying metal in powder form in amount of 0.3-3.0% of weight of rectifying metal salt in melt; and interaction of additive with melt and material of reactor to form intermetallic protective coating on reactor internal surface. Rectifying metal is used in the form of tantalum or niobium, and halide of alkali metal is used in the form of sodium or potassium chloride. Contamination of rectifying metal powder with metallic impurities, particularly, with nickel preset in reactor material is reduced by factor of 3-5 with increased powder surface value by 10-40%. In addition, content of oxygen in powder is reduced by factor of 1.5-2.0. EFFECT: higher quality of rectifying metal powder. 3 cl, 1 tbl, 3 ex