METHOD OF GALVANIC METALIZATION OF MOLYBDENUM ALLOYS Russian patent published in 2018 - IPC C25D5/10 C25D5/28 C25D5/38 

FIELD: technological processes.

SUBSTANCE: invention relates to the field of electroplating, in particular to the electrolytic coating of copper and tin-bismuth alloy on molybdenum alloys. Method includes electrochemical degreasing of parts, anodic etching, electrodeposition of the intermediate layer, which increases the adhesion of electroplating coatings, while in one universal electrolyte consisting of copper sulfonic acid 2–3 % and sulfuric acid 45–65 %, having an electrolyte temperature of 70–80 °C, anode etching is performed at anode current density of 10–30 A/dm² for 2–4 minutes, then, without removing the electrolyte parts, the polarity is changed, the electrolyte is stirred and a current is pumped with a cathode current density of 8–10 A/dm² for 0.5–0.7 minutes, then the cathode current density is set to 0.5–2 A/dm² and the electrodeposition of the intermediate layer is carried out for 4–6 minutes, then the details are transferred to the sulfuric acid electrolyte of thinning consisting of copper sulfate 200–250 g/l and sulfuric acid 50–70 g/l, in which a copper coating is grown at a cathode current density of 1–3 A/dm² up to a thickness of 6–12 mcm, after that, the parts are washed and a coating of tin-bismuth 6–12 mcm thick is applied to the copper coating with a cathode current density of 0.5–2 A/dm² from electrolyte containing, g/l: tin sulfuric acid 40–80, sulfuric acid 100–120, bismuth sulfate 0.5–1.5, preparation OC-20 4–5.

EFFECT: reducing the number of operations, increasing productivity, using affordable equipment, using more environmentally friendly substances, reducing the percentage of rejects, increasing the adhesion of coatings to molybdenum alloys and improving solderability.

1 cl, 3 ex