Application of an alternative current in the processing of cobalt-containing nickel-based alloys

The versions of electrochemical processing of multialloyed nickel-based alloys are studied. These are the processing of the compositions (wt %) 57.0–70.0 Ni, 5.0–10.5 Co, 8.0–20.0 Cr, 1.2–5.0 Mo, 5.0–11.0 W, 2.0–2.9 Ti, 0.8–1.2 Nb, and 5.1–6.0 Al using an industrial-frequency alternating current and sulfuric acid electrolytes, namely, the dissolution of Ni-(10.0–15.0 wt %) Co alloys resulting from primary pyrometallurgical refining and direct dissolution. The rates of electrochemical dissolution of multialloyed nickel-based alloys under the action of a direct current and an industrial frequency (50 Hz) alternating current and the current efficiencies of the processes as functions of the temperatures and concentrations of sulfuric acid in electrolytes are compared. The optimum conditions of alloy dissolution are determined, and large laboratory studies are performed. A principal scheme of ac processing of the alloys is suggested.