Abstract: There is disclosed an electroplating apparatus in which a plurality of anodes and twice-as-large plurality of first and second cathodes are disposed in a cell such that each anode has on its opposite sides a first cathode and a second cathode, respectively. First and second adjustable constant current sources supply current to, respectively, all first cathodes and such anodes and all second cathodes and such anodes. A plurality of current adjusting units respective corresponding to the anodes are connected on the positive side of each such current source between that source and each respective anode. The anodes are permanently installed in the cell, while the cathodes are carried by a holder fitting over the top of the cell and removable therefrom. The cathodes may be selectively inserted into guideways in their holder and then locked in place in these guideways until removal of the cathodes is desired, when they are unlocked.

Abstract: Improved electroplating processes and equipment, in which an inert gas (21) is mixed with a liquid electrolyte (20) to form a foam (23) of the gas plus electrolyte, which foam is then circulated (arrows A) through an electroplating chamber (30) in which anodes (12) and cathode substrates (10) are mounted so as to plate a metal from the foam electrolyte onto the cathodic surfaces of the substrates. Preferably, the gas is nitrogen or argon and the electrolyte may be any of various conventional plating solutions, such as a potassium gold cyanide solution in a specific example of a gold-plating process described in detail. The foam process provides improvements in uniformity of the thickness of the plated metal and in the surface appearance.