The leveling in nickel plating was studied with a Hull Cell. In dull nickel plating from Watts bath, the leveling was found to be affected by “Geometrical leveling”. In bright or semibright nickel plating from a high temperature bath with a highly concentrated leveler, a good leveling was obtained at high current densities, but the leveling at low current densities was little made. Therefore, the concentration range of the levellres and bath temperature must be carefully chosen for practical bright and semibright nickel plating baths; In bright and semibright nickel plating from a low concentration nickl bath with a leveler of low concentration such as a bath of the composition NiSO₄ 7H₂O 75g/l, NiCl₂ 6H₂O 110g/l, H₃BO₃ 30g/l, the leveling was found to be made more than that from the Watts bath.

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This study has been made as a part of studies of electrolytic descaling of iron and steel in neutral electrolytes. In this report the descaling conditions of annealed SUS 430 steel and tis behaviour in electrolytes of sodium chloride and sodium nitrate were experimentally investigated. Results obtained are given in the following: In NaCl electrolyte, no dissolution of the scales on the steel was found, but some parts of the metal substrate exposed to the electrolyte through some scale defects dissolved in the electrolyte. Therefore, layers of the scales were removed by means of separating from the base metal during the electrolytic descaling process. In NaNO₃ electrolyte, layers of the scales were removed by the dissolution of a Cr-oxide of the scale during the electrolytic descaling process. In the NaCl solution, a large number of pits were formed by Cl^- ions on the descaled parts of the surface of the steel with no glossy appearance, while, in the NaNO₃ solution, less pits were formed on the descaled surface. The surface in the latter solution had a well descaled glossy appearence at high temperatures.

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The life and performances of gas turbine engines are greatly damaged by the oxidation, sulphidation, and hot corrosion of the surface layer of the blades. Recently, protective coatings of superalloys on the blades have been frequently attempted to improve them. We have designed and constructed a sputtering apparatus with two targets facing each other to deposit magnetic films on the blade alloy at a very high rate with no extreme rise in substrate temperature. Protective coatings of superalloys of the (Co, Ni)-Cr-Al-Y system of ferromagnetic properties at high rates have been made under various sputtering conditions. Films of above 4μm in thickness were deposited at a rate of about 3000Å/min with the two circular targets of the same composition and of 58mm in diameter. This deposition rate is about 30 times as high as the rate observed in conventional diode sputtering techniques. The films deposited in the argon atmosphere of the pressure below 5×10^-3 Torr were adherent to the substrate and crack-free even after annealing at 900°C. In addition, the films exhibited neither any structural imperfections such as spits, flake and linear defects nor any columnar structure. These results show that this sputtering method can be practically used to deposit the superalloy films on the blades of gas turbine engine for protective coating purposes.

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Electrodeposition of resin by rectangular pulse current was studied in acrylic paint solutions. Analyses of responsed potential-time curves to the applied current revealed an inductance term as a nonfaradaic portion. The inductance calculated from the potential-time curve varied from 0 to 300 (mH-dm²) with resin concentration from 0.01 to 32%. In order to interprete the inductance observed at paint deposition stage, the coulombic yields, required bath voltage, and the properties of deposited paint film, such as tackiness and corrosion resistance, were measured at various resin concentrations and the observed inductance is tentatively interpreted in terms of the morphology of the resin particles.

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