The effects of surfactants of the polyoxyethylene family on the hardness of copper electrodeposited from an acid copper sulfate bath were examined as a function of Cl^- concentration. Factors determining copper hardness were examined by analyzing the microstructure of copper deposits by X-ray diffraction, and by potentiostatic measurement of the potential-current curves for copper deposition and dissolution. Rough deposits with the preferred (110) orientation were formed at concentrations lower than 1mM Cl^-, while at higher concentrations fine grained copper without a specific preferred orientation was deposited. The hardness of copper deposited in this solution system was found to increase with increasing deposition overpotential.

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A thick anodic oxidation coating on aluminum cannot be produced in a sodium carbonate bath be due to the formation of a barrier-type layer. This study was carried out to investigate the formation of thick film in a concentrated sodium carbonate solution containing tartrate and fluoride. It was found that a porous anodic oxidation coating was formed at current densities of more than 2A/dm² in a high concentration bath of sodium carbonate solution containing sodium tartrate (0.3M-1.0M Na₂CO₃, 0.1M-0.15M NaF, 0.1M-0.2M Na₂C₄H₄O₆). In the films produced did not cracking sound occure, even when bent at a greater angle (90°) in a bending test, and hair cracking on the surface of the flexed film could not be observed with the naked eye. Results of the scratch hardness (load: 50g) and the bending test indicated that film formed in sodium carbonate-fluoride system bath was softer than film formed in sulfuric acid bath. It was concluded that the flexibility of the above film was caused by the fluoride content of the film, the unevenness of film surface, and the larger size of pores and cells compared with the films formed in sulfuric acid bath.

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The high-speed electrodeposition of nickel in a fundamental Watt bath was investigated using a device in which the electrolyte was moved up perpendicularly by a suction pump through a nozzle to the cathodic surface. This made it possible to obtain a normal deposit at current densities as high as 350A/dm² using one nozzle, and as high as 200A/dm² using three nozzles. It is considered that high speed deposition on large cathode areas is possible using this multi-nozzle suction flow method. Polarization behavior on the cathodic surface, electrolyte flow and other factors were investigated and discussed.

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