High Speed Electrodeposition Research Articles

Characterization of New Corrosion Resistant Nickel‐Zinc‐Phosphorus Alloys Obtained by Electrodeposition

The electrodeposition of a family of coatings was studied at a rotating cylinder electrode by varying the temperature (45°–80°C) and the applied current density (0.03–0.95 A/cm2). Two of the coatings were nickel‐rich, two were zinc‐rich, and a fifth coating had approximately equal amounts of Ni and Zn. The coatings were characterized using SEM/EDX and Auger depth profile techniques. A Ni‐rich alloy with a supersaturated amount of zinc and the approximate composition 59Ni‐39Zn‐2P was obtained at all temperatures in the high speed electrodeposition current density range 0.6–1.0 A/cm2. The supersaturated alloy could be deposited at current efficiencies higher than 80% at all temperatures. The corrosion rate of this coating, estimated from polarization resistance measurements in 5% at pH 5.0, was the lowest among the various coatings.

吸引流法によるニッケル高速電着の研究

吸引流法によるニッケル高速電着の研究

The High Speed Electrodeposition of Sn/Pb Alloys

The electrodeposition of Sn/Pb alloys and the effect of surface agents was studied in fluoboric acid solutions. Smooth, semibright deposits have been produced at current densities in excess of 800 mA/cm2, approaching the mass transfer limited current. Dendrite suppression (microleveling) has been achieved by the addition of polymeric sulfactant and uniform current distributions have been obtained by the addition of lactones or other related species. When the two adsorbed species are used simultaneously the solution concentration of metal ions and the additive ratio dictate the deposition parameters. The additives have been found to be chemically more stable, less costly, and allow current densities in excess of 20× those in current commercial use.

High Speed Electrodeposition of Chromium from Low Concentration Chromic Acid Solutions

The presence of trichromate ions in the chromic acid solution is required to obtain a cathodic film from which metallic Cr may be deposited. With a high flow rate plating system, it was predicted from this proposed mechanism that bright, smooth, adherent deposits of Cr can be laid down on Cu or Fe substrates from solutions as dilute as 25 g/liter but no deposit from 1 g/liter. A high speed plating process (HSP), based on an air pressure flow system (APFS) propulsion of electrolyte through a narrow gap between the cathode and anode separated by about 4 mm, was used to plate chromium metal on copper samples at rates up to 50 times faster from solutions 5 times as dilute as conventional chromium plating techniques. The HSP system, the APFS descriptions, and some selected results are presented.

High Speed Electroplating—A Review of the Subject

SummaryIn this paper the fundamental and practical problems of high speed electrodeposition are considered. Some of the processes which have been developed for high speed plating are examined and their advantages and shortcomings discussed.

High Speed Electrodeposition of Copper from Conventional Sulphate Electrolytes

A rotating cylinder cathode cell has been developed to examine parameters affecting high rates of deposition in copper sulphate based electrolytes. Initial electrochemical measurements have shown t...