Copper alloy cleaning process
AssigneeOlin Corporation
InventorsMichael J. Pryor, Murray A. Heine, Andrew J. Brock
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Abstract
A rapid and effective surface cleaning process for copper alloys, particularly copper alloys containing aluminum and other metals tending to form surface coatings of refractory oxides during annealing treatments, consists of treating such alloys or articles fabricated thereof for a short time in a hot aqueous solution of an alkali hydroxide, rinsing with water, and then immersing for a short time in a hot aqueous solution of ferric sulfate, or other ferric salt of a mineral acid, followed by rinsing with water.
Claims10
A process for cleaning the surface of a copper base alloy having a surface layer of thermally formed complex metal oxide of a refractory nature which is resistant to ferric sulfate, said process comprising immersing the said surface in an aqueous alkaline solution having a pH of 11 to 14 and heated to a temperature of about 40.degree. C. to its boiling point for a period of two seconds to not more than ten minutes, and then immersing the said surface in 0.5 to 3 N. aqueous solution of ferric sulfate containing no added mineral acid at a temperature of 25.degree. C. to 95.degree. C. for a period of two seconds to not more than five minutes, said process being adapted to remove said surface layer from the copper base alloy surface when said surface layer has a thickness up to at least 160 A.
Dependencies are inferred from the claim text.