METHOD OF REFINING COPPER AND COPPER-BASE ALLOYS Russian patent published in 2002 - IPC

FIELD: metallurgy of nonferrous metals, particularly, production of copper and copper alloys. SUBSTANCE: method includes induction melting, uniform introduction into melt, in process of melting, refining fluxes based on polymethaphosphates of alkali metals with addition of cupric oxides, removal of slag. During melting silicon dioxide is additionally introduced into melt in amount of 20-80% of total consumption of fluxes. Silicon dioxide is simultaneously introduced with flux in amount of 10-50% of total weight of silicon dioxide addition, and remaining part is introduced 15-20 min before slag removal. Silicon dioxide is used with its particles sizing up to 2 mm. EFFECT: increased required purity of metal, higher its quality and reduced amount of refuse. 2 tbl, 1 ex