ZINC-NICKEL ELECTROPLATING

摘要

The present invention relates to an apparatus (12) for applying a zinc-nickel electroplate to a workpiece. The apparatus comprises a zinc-nickel electroplating bath (16) comprising an amine additive, such as poly(alkyleneimine), which is capable of being oxidized in the bath to cyanides. The bath has a pH more than about 14. A cathode workpiece (18) is positioned in the bath. An anode assembly (20) is also positioned in the bath. The anode assembly comprises an enclosure (22) defining an anolyte compartment (24), at least a portion of the enclosure being an ion exchange membrane (26). An anolyte (28) is positioned in the compartment. An insoluble metal anode (30) is immersed in the anolyte. The anolyte is a conductive salt or base solution and the anode is a metal or metal coating selected from the group consisting of nickel, cobalt, iron, chromium and alloys thereof.