Wednesday, April 2, 2008

Nickel Iron and Nickel Fluoborate Baths

Nickel-Iron Baths
Nickel-iron plate and its magnetic and decorative properties will be discussed extensively in the next articles.

Nickel-Flouborate Baths
Nickel-floubarate plating baths have some unique qualities which make them applicable for a number of uses, despite the higher initial cost of the electrolyte. Control of the flouborate baths is very simple; it usually involves only a specific gravity reading and a pH determination. The bath is buffered more highly than the conventional sulfate or chloride baths. As a result, changes in pH during operation are not as rapid. Nickel flouborate has high solubility, allowing the use of nickel concentrations far above those possible in chloride-sulfate solutions. This characteristic, along with high conductivity and excellent anode corrosion over wide variations in conditions, permit high current densities to be employed at reasonable voltages. Other favorable characteristics are freedom from sludge formation and higher tolerance to metallic impurities.

The deposits are light in color, ductile, and smooth and do not tend to tree or show nodule formulation at higher current density areas. Their internal stress is even lower than that of deposits from the Watts bath. Nickel-flouborate bath are used for facing stereotypes. Other applications are for the production of electrotypes, electroforming, barrel plating, and the drawing of nickel-plated copper wire.

Titanium anode baskets cannot be used, and the solution is also very corrosive to lead and high silicon cast iron. Silica containing diatomaceous earth filter aids cannot be used, but pulp is satisfactory.

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