摘要 |
FIELD: metallurgy. ^ SUBSTANCE: procedure consists in production of copper melt, in refining melt from volatile oxides and other impurities, in deoxidising with carbon, in refining in deoxidised condition, in casting metal into ingots and in crystallisation. Also, before melting charge materials out of copper are subjected to surface etching. They are melt in a graphite crucible on bottom of which there are placed lumps of graphite at amount equal to 0.15-0.6 % of copper charge weight. In the process of melt refining melt is repeatedly mixed with currents of industrial frequency during every 3-15 minutes. ^ EFFECT: reduced prime cost of ingot production of super-pure copper for super-conducting materials out of oxidised copper charge materials and upgraded quality of ingots; stable relative residual resistance RRR of produced material in annealed condition of not less, than 200 units. ^ 2 cl, 1 tbl, 3 ex |