Improvements in or relating to the electrodeposition of nickel, cobalt, and nickel-cobalt alloys

摘要

687,275. Electrodeposition of nickel, cobalt, or nickel-cobalt alloys. WESTINGHOUSE ELECTRIC INTERNATIONAL CO. Sept. 20, 1949 [Oct. 12, 1948], No. 24160/49. Drawings to Specification. Class 41. A process of electrodepositing on a member a metal from the group consisting of metal, cobalt and nickel-cobalt alloys comprises the steps of dissolving in the electrolyte cadmium in an amount of between 0.1 and 0.005 ozs. per U.S. gallon of electrolyte, causing an electric current to flow through the members while in the electrolyte, for a period of time of not over two seconds to electroplate metal on the member, then causing a de-plating current to flow, of a magnitude and for a period of time to deliver at least 4 per cent of the contents delivered during the preceding plating period, and continuing applying the alternate plating and deplating current until a desired thickness of metal has been electro-deposited on the member. The electrolyte may, for example, comprise between 10 and 60 ozs. per gallon of at least one salt of a metal from the group consisting of nickel and cobalt, between 0.1 and 0.005 ozs. per gallon of cadmium, and between 1 and 10 ozs. per gallon of boric acid, the pH value of the solution being between 2 and 5.8. The cadmium may be introduced into the bath as a cadmium salt, suitable salts being the chloride, iodide, nitrate, oxide, sulphate and bromide, or it may be provided as a separate anode of cadmium or as part of an anode consisting mainly of nickel, cobalt, or nickel-cobalt. The plating period may be less than half a second and the de-plating period may be from one-half to one twenty-fifth of the plating period. Reference has been directed by the Comptroller to Specifications 630,165 and 642,101.