The author studied the effects of cutting-down buffing with sewed sisal buffs on polishing abilities for various kinds of stainless steels.
The results obtained were as follows.
(1) The capacity of buffing for 18Cr-8Ni stainless steel was larger that for 13Cr and 18Cr steels under the same conditions of cutting-down buffing.
(2) The strength (rigidity) of buff depended upon the melting points of fats blended in grease-base buffing compounds as well as the peripheral speed of wheel. Then, it was concluded that the relation between buffing abilities and strength of buff should be studied.

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Current distribution was examined by applying direct current in the vertical type electrolytic cell containing sulfuric acid with an anode of a long aluminum sheet. It was carried out by the measurement of thickness of anodic oxide coating and color difference in dyed specimens and by the observation of burnings of anode.
Current distribution was more uniform when the concentration of acid was higher, the concentration of aluminum was lower, anodizing temperature was higher, anode current density was lower, and circulation velocity of electrolyte was higher. When the current density was extremely bad in uniformity, current passed through a certain point, at which burnings were produced. Shape and size of burnings would depend upon convection of heat generated on the anode. The two step raise of the current at the early stage of anodizing was effective for preventing the production of burnings. Moreover, studies were also made on the effects of arrangements of the electrodes.

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Effects of mechanical deformation of steel substrates on electrodeposition of tin from stannous sulfate bath have been studied by means of microscopic examination of deposited tin nuclei.
Annealed and skin-passed cold rolled steel sheets were used for substrates for examination. The sheets had been buffed, etched with nitric and picric acid-alcohol solution, or subjected to cathodizing in alkaline solution prier to the electrodeposition.
It was found that the deformation such as tension or deep drawing had no remarkable effects on the number of nuclei formed and on the regions of nucleation spots.
These results seem to correspond well with Pick's observation in copper electrodeposition on copper substrate from copper sulfate solution; that is“Series of dislocation produced by mechanical deformation can not influence on initial formation of the deposit or on the provision of nucleation centres.”
Furthermore, it was found that tin nuclei were also formed in the interier of crystal grains of steel substrate when the steel sheet was cathodized in hot alkaline aqueous solution.

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Experiments were carried out to determine the anodizing condition of low temperature hard anodizing process, under which a uniform oxide coating was formed, and also to examine the mechanism of local corrosion of anode.
Commercial aluminum sheets such as 99.99% Al, 1100, 2017, 4043 and 5052 were used as specimens. Each sulfuric acid of 1, 10, 20, and 40%, containing aluminum sulfate equivalent to each 1/10 of the acid in concentration, was used as an electrolyte. The current density was 0.1-8.0amp./dm² and the temperature of the bath was kept constant at 0.5°C for each electrolyte. The surfaces of anodized specimens were observed on microscope, electron microscope and scanning electron microscope, and their roughness was determined. In conclusion, it was preferable that electrolysis would be carried out in the acid of high concentration under low current density for the purpose of preventing local corrosion of the anode.
When anodizing was performed under high voltage in a bath, in which solvent attack against the anodic coating is relatively weak, current passed preferentially through weak points of barrier layer of the coating to provoke the propagation of pittings or burnings of the anode.

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In the previous papers, the author reported that leveling action was little affected by sorts of bath (K⁺ and Na⁺), concentrations of copper and free cyanide in the bath, temperature of bath, stirring, and addition of sulfur compounds, etc. depressing cathode polarization; but, the application of periodic reverse current and, in particular, its combination with stirring obtained more effective results.
In this paper, with the object of investigating the leveling mechanism of P.R. current, the effects of ratio of currents between normal and reverse, current density, reverse current density, and the above additives were determined.
The results were summarized as follows.
1) The leveling action on copper deposits was more improved with the increase in metallic copper concentration, decrease in free cyanide concentration, etc. which increased anode polarization. (However, these effects were very little in D.C.)
2) Leveling action was improved by stirring of bath, but there were little effects of bath temperature.
3) Leveling action was generally improved with the increase in time and density of reverse current.
4) Additived containing metals, which co-deposit with copper, depressed the leveling action, but the addition of compounds containing sulfur, which can easily be freed, improved the action. Addition of most of organic compounds had little effects on leveling. However, in any baths with additives, the action was improved by stirring.

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