The effect of co-deposited lead on the property of electrogalvanized steel sheets after heat treatment was studied, especially from the viewpoint of adherence of the zinc layer. In the process of alloy formation between the deposited zinc and steel sheets by heat treatment, the co-deposited lead atoms concentrate at the interface between the zeta-phase layer and the zinc layer, and thus restrain the formation of the alloy layer. The peel-off phenomenon of the zinc layer were found when the quantity of the alloy layer exceeds a certain limit which is defined as ξ al. This value decreases with an increase in the lead concentration of the deposit. It is supposed that the lead atoms concentrated at the interface accelerate the formation of cavities as a result of the gathering of vacancies, and that, the peel-off of the zinc layer is due to the accelerated Kirkendall effect.

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TiO₂-Ni composite electrodes were prepared by dispersion plating to make a photosensitive electrode with a high efficiency and ease of production. Composite layers of Ni matrix containing dispersed TiO₂ were deposited electrolytically on substrate metals from a Watts type nickel electrolyte containing the TiO₂ particles suspended in the solution. The electrodes were kept under 10^-5 Torr at 750°C for different periods to partially reduce TiO₂. The optimum time for the reduction was 15 to 30 minutes. A photovoltage vs. pH plot showed a linear relation with ΔE_photo/ΔPH=-60mV for the alkaline solutions investigated. From linear scan voltammograms, the dissolution of Ni matrix through the passivation layers was observed, even in alkaline solutions. A delay in the increase in the photovoltage was interpreted as photogenerated positive holes being consumed by the oxidation of water and Ni at the electrode interface. These composite electrodes showed the photovoltaic behavior similar to a TiO₂ single crystal electrode in alkaline solutions. In acidic solutions electrochemical dissolution of the Ni matrix increased.

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Electroless TiC coating on steels from a molten salts bath has been studied. The effective TiC coating appears to be possible when the content of the mobile carbon, which is defined as an uncombined carbon with alloyed metals in steel, is greater than about 0.8%. For the steels with lesser mobile carbon, carburizing processes have been applied. In the case of gas carburizing by butane the carburized steel could be coated with TiC from the usual bath that we have proposed. In the case of liquid carburizing by BaCl₂-NaCl, on the other hand, addition of NaCN was needed. The effect of the additive was attributed to the suppression of carbon diffusion from the substrate to the bath.

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Current wave forms in A. C-E. D for six types of practically used electrodes have been measured in an acrylic paint solution, to obtain coulombic yields, electric power consumptions, and deposition rates of the paint. It has been shown that the electrodes acting as rectifiers and condensers have high paint deposition rates and low electric power consumption. The properties of the electrodes for A. C-E. D have been attributed to electric current flowing in the direction inverse to that of external A. C. voltage applied for the effective deposition of the paint.

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