METHOD OF POLISHING COPPER AND COPPER-BASE ALLOYS Russian patent published in 1999 - IPC

FIELD: electrochemical treatment; may be used in process of electropolishing in various fields of engineering such as electrical engineering, instrumentation engineering for decorative purposes in manufacture of consumer goods from copper and its alloys. SUBSTANCE: at the first stage a part is treated for 3-10 min with voltage of 300-360 V and temperature of 60-90 C in solution containing ammonium phosphate in the amount of 3-5 wt.%; phosphoric acid up to attaining pH 5-7; water, the balance. At the second stage, treatment lasts for 10-30 s with voltage of 320-360 V and temperature of 70-90 C in aqueous solution containing, wt.%: ammonium phosphate, 3-5; potassium, sodium tartrate, 1-3; water, the balance. EFFECT: extended technological potentialities due to treatment of nonferrous metals and alloys; reduced aggression and toxicity of electrolytes.