- Copper cyanide strike for steel - "Woods" Nickel strike for stainless steel - Activates to plate nickel on nickel chromium on chromium

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1 Plating Hydrogen by Arthur Wasserman Plating Hydrogen? Cathodic activation examined with reference to the cold fuslon developments (controversy). Historically cathodic activation has been used for plating preparation of passive (oxide) surfaces e.g. nickel/chromium alloys, niobium and powdered metals. More recent results of work employing cathodic activation for preparing aluminum for plating will be presented e.g. process parameters, deposit adhesion; suggesting a mechanism of oxide reduction. Data on theoretical energy requirements to reduce oxide will be given. The cathodic activation Joule energy input used in this work on aluminum was considerably less than the theoretical energy required to reduce oxide. In the spirit of a common sense Baltimore AESF approach a simplified environmentally improved method of chromium plating aluminum will be discussed. The process is based on cathodic activation (reduction of surface aluminum oxide) to achieve an adherent electro deposit. Also the mechanism of cathodic hydrogen has lead the author to stay current with the work being reported outside the plating industry as "cold fusion" which claim excess energy from cathodic hydrogen. History of Cathodic Reduction The industry uses baths with low plating efficiency which results in significant hydrogen evolution e.g. 98%. - Copper cyanide strike for steel - "Woods" Nickel strike for stainless steel - Activates to plate nickel on nickel chromium on chromium - Activate niobium for plating - Activate aluminum for plating Theory of Cathodlc Hydrogen Reduction As Applied to Aluminum Formation of hydrides at cathode' AL / e H- H - H. ' - AL H, + H- + AL H,- AL H,- + H+ -+ AT0 Van der Walls Forces Covalent Bonds Here is a possible explanation for achieving necessary temperature to cause aluminum oxide reduction. At low or normal temperatures, hydrogen will not reduce aluminum oxide. An additional reaction is necessary to provide the extremely high temperatures required. However, a study of the variation with temperature of the free energy of metal oxide formation (Fig. 1) indicates the mechanism wherein hydrogen can reduce aluminum oxide at elevated temperatures. By examining the curves in Fig. 1, any metal reduces the oxide of a metal whose curve lies below. When the net change in free energy is negative, as traced in Fig. 1, oxide reduction takes place. The free energy gets more negative with increases in temperature or stays basically flat, with very little change, thereby intercepting the aluminum line at some elevated temperature (N55OoC). 1

2 , chloric acid plus inhibitor at ampere minute per square cm. (3-5 ampere minute per square inch) at 60-7OoF 4. Cold water rinse 5. Chrome plate Chromic acid/sulfate F 0.15 ampere per square centimeter (1 ampere/inch square) at inch per hour deposition rate 6. Bake 10 minutes at 400oF. Applications (hard chromium) - superior adhesion - see Figures 2, 3 and 4 on Molds, Capstans, Chutes, Wearing Parts Assorted. Possible Application - Decorative. Aluminum automobile wheels. To enhance marketability with environmental sound process, No copper, cyanide, zinc, tin or nickel effluent to treat. Temperature ( C) Fig. 1. The variation with temperature of the free energy of metal oxide formation., Therefore the reaction A40,+ H, -+ A L requires ~ a temperature of 550.C. Process parameters for plating on aluminum are given in Wasserman s Patent 2,888, Liquid slurry hone with aluminum oxide e.g. 180 mesh 2. Cold water rinse No Nickel Plate is Used Results in superior adhesion and corrosion resistance. Waste Treatinq Separate aluminum oxide abrasive. Reuse until mesh size is reduced beyond being functional; reuse water from slurry. Rinse from cathodic activate - Neutralize with soda ash -+ sodium chloride Chromium Treat - current technology. Disadvantaaes color. Thicker chromium deposit required for 3. Cathodic activate in 10% hydro

3 Fig. 2 Example of specimen after bend test (190 degrees) used to check adhesion. -m. hammer to check adhesion of chromium on aluminum. Questions came up after the publication of, my article in fusion technology stating that the reaction may not be: Equation 1 AL,O, + H, + AL H, which requires a temperature of 550oC according to Free Energy Calculation. But the reaction is: AL,O,+ HCL + ALCI, 1 +H, A L or ~ ALH, To demonstrate that Eq. 1 is the mechanism a simple experiment was devised. Flg. 3 Example of specimen after nail test to check adhesion of chromium deposit

4 Using 18-8 stainless steel: Process #1 Alkaline clean immersion 10% HCI Immersion - 1 minute at 65oF Nickel Plate Process #2 Alkaline clean immersion (same conditions) Cathodic 10% HCI 5 Ampslsquare inch for 1 minute Nickel Plate (same conditions) Process #2 gave superior adhesion also when the experiment was done on aluminum prior to chromium plating cathode activation resulted in superior adhesion of the chronic deposit indicating that cathodic hydrogen was required to give sufficient activation (oxide reduction). Other Applications of Cathodic Hydrogen Authors work on cathodic activation on metals prior to electroplating kept the author curious about reports on "cold-fusion'' which after all can be considered as cathode activation or possible plating of hydrogen on the surface or the intercedes of palladium, platinum or nickel cathodes. There are "many" reports of excess energy and atomic particles from "cold-fusion" cells. Refer to Cold Fusion Patent News through 2/94 - Cold Fusion p 75 vol No 1. The work that is probably most interesting to platers is that of: Fleischmann & Pons, J. Electroanalytical Chemistry: (1969). Lithium Chloride Platinum Electrodes. Mills & Kneizys - Fusion Technology - vol 21 Mar Excess Heat from Potassium Carbonate Nickel Electrode. Wasserman - Fusion Technology, vol 21 Mar Cathodic Reduction - Sodium Chloride Aluminum Electrodes. Paterson Power Cell - Cold Fusion vol 7 US Pat 5,372,688. Cathodic Hydrogen Electrode Thin Palladium Plated Plastic Pellets. Notoya, Noya & Ohnishi - Fusion of Technology vol 21 Mar Excess Heat and Nuclear Particles from Potassium Carbonate Nickel Electrodes. The suggestion of Fleischmann et al. basically is that hydrogen at the cathode or in the cathode fuse: H' + H' -+ H, (Fusion Reaction) the criticism is that this reaction violates Coulombs: Low - Like charges repeat and if it takes place you have to get prescribed atomic particles that fusion physics has documented. Some experimenters can't find atomic particles. Others that find them do not conform to the well tested mechanism known to atomic physicists. The workers in this field generally counter: (1) other mechanisms are possible (2) that atomic physics has a vested interest in government finding for billions in fusion reactors and no 2-bitt electrolytic cell can accomplish fusion. However, as this paper attempts to show cathodic reduction (activation) in the electroplaters' experience has achieved results that theory suggests can be only achieved at elevated temperatures not possible in conventional plating baths. Interesting

5 Concluslon 1. Cathodic hydrogen activation (oxide reduction) can be used to achieve a simplified, reliable environmental f riendly cycle to achieve functional and decorative chromium plating on aluminum. 2. Cathodic hydrogen reduces aluminum oxide at possible elevated temperatures (e.g ) preparing the surface for electrodeposition. 3. Cathodic hydrogen presents some interesting possibilities. References 'Wilberg, E. and Ammberger, E., Hydrides of the Elements Group l-lv, p. 381, Elsevien, New York, *King, F., Aluminum and its alloys, p. 48, Ellis Harwood Chichester (West Sussex) and New York,