METHOD FOR PRODUCTION OF TUNGSTEN POWDER Russian patent published in 1995 - IPC

FIELD: powder metallurgy. SUBSTANCE: preliminarily powder of tungsten trioxide is ground to subgrain state and reduce at different temperatures under conditions similar to those under which mixture of tungsten trioxide with tungsten metal is reduced. In this case, relation d_o= f(t) is obtained. Series of nomographs is constructed. Nomographs are used to determine process parameters d_w,, t, x, C_w depending on necessity to produce tungsten powder of required average size and maximum productivity. Temperature of preliminary reduction is 600-900 C. Product of preliminary reduction is mixed with powder of tungsten metal whose grain average size and mass fraction in mixture are determined by nomographs. Mixing is carried out simultaneously with grinding. Produced mixture is subjected to final reduction. EFFECT: higher efficiency. 3 cl, 10 dwg, 10 tbl