The electrodeposition of Fe-Zn alloys was interested in the properties of deposits and the mechanism of their deposition. Although many works have been contributed to the studies on this deposition, its mechanism has not yet been clarified.
Standard single electrode potential of Zn in single salt solution is less noble than that of Fe. However, it was noted that Zn preferentially deposits under a certain plating condition. It suggests that the type of these alloys is formed by anomalous codeposition.
In this paper, the effects of plating factors upon the composition of the deposits from chloride solutions are investigated in order to clarify the mechanism of anomalous codeposition.
The composition of these alloys was a function of many factors. The main factors included bath composition, total ion concentration of metals, current density, temperature, and pH of the bath. Transition current density for anomalous codeposition was determined by these results.
On the other hand, it was found that there is a transition point of bath composition, at which the type of deposition changes from anomalous to regular. The point depended on temperature, but not on current density.

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In order to reduce the cost for gloss-buffing, the author studied the effects of various abrasives of grease-base buffing compounds.
The results obtained were as follows:
(1) It had already been found that the average grain size of chromic oxide having suitable gloss-buffing effects was 0.4-0.5μ in diameter; however, the addition amount of aluminum oxide having larger grain size to the compound was permitted up to 40%.
(2) The condition for giving the most suitable gloss-buffing effects in the seexperiments was as follows; the average grain size of aluminum oxide was 9μ in diameter and the addition amount of lauric acid for mixing with it was 17%.
(3) It was found that other abrasives softer than chromic acid, for example, talc and others, were unsuitable for gloss-buffing of stainless steels.

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Only mannitol or glycerine is generally used for the determination of boric acid in a nickel plating solution in order to make its acidic property so strong that it can be titrated with NaOH. However, these solutions give very ambiguous color change of indicator due to the precipitation of nickel salts. Therefore, only experienced chemists or well trained workmen can accurately confirm the actual end point of the titration. For eliminating such interference of nickel salts and easily confirming the end point by any persons, the author attempted to find out a solution which produces no precipitates during the titration in these experiments; and also, he tried to furnish the reason for ambiguousness in titration.
The following results were obtained after many experiments.
(1) In any titrations which produce nickel salts such as Ni(OH)₂, the salt is formed until very approximate to the end point, which shows some error by the consumption of titrant (NaOH). Then, the pink color of phenolphthalein is absorbed by Ni(OH)₂ and the pH jumping at the end point is also diminished to as little as less than 15% of the total phenolphthalein pH range.
(2) Known methods by complex salts of citrate, which do not produce precipitates of Ni(OH)₂, are also not very satisfactory; because, the pH jumping at the end point is only about 35% and the color change of phenolphthalein is from blue-green to purple-red.
(3) New methods by complex salts of oxalate were attempted in these experiments. They also did not produce precipitates of Ni(OH)₂ and were very satisfactory in color change at the end point; because, the pH jumping at the end point was about 65% and the color change was from blue-gree to purple-red. In these methods, analytical cost was minimized by the use of less amounts of cheaper chemicals than the conventional citrate complex methods. The mixture of chemicals used was composed of 37g/l if sodium oxalate (Na₂C₂O₄·5H₂O), 2g/l of phenolphthalein, and 400ml/l of glycerin. The accuracy of analysis was within the error of 0.5%.
(4) The procedure of analysis was as follows. One ml of nickel plating solution was taken out and to it were added 20ml of water and 20ml of the above mixture for the indicator. The solution was titrated with 0.1N NaOH. The quantity of boric acid was calculated by the following equation.
Boric acid (g/l)=6.184×F×ml

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The anode process was studied in electrodeposition of water soluble paints (which are composed of alkyd and acryl resins, but no pigments) on plates of steel, aluminum alloys, and copper.
The following conclusions were drawn.
(1) The total resistance (R) in the circuit for electrophoretic coating was expressed by the following equation:
R=R₁+R₂
where R₁: Resistance of oxide film (including that of the film in passive state)
R₂: Resistance of deposited film
R₁ and R₂ were variables depending on the kind of paint used, and they also varied according to anode materials for the same kind of paint.
(2) The state of anode surface during electrodeposition corresponded to one of the folowing four items.
a) Being covered by passive film and visible oxide film.
b) Being covered by visible oxide film only.
c) Being covered by passive film only.
d) In active state, being covered neither passive film nor visible oxide film.
(3) Most of anode metal, which had been dissolved during electrodeposition, was occluded by the coated film, which resulted in the increase of its electric resistance.

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Electrodeposition of W-Co alloys from aqueous solutions was studied by means of cathode potential measurement, X-ray diffraction, and transmission electron microscopy in order to investigate the relations between deposition potential and properties of deposits such as crystal structure, tungsten content, and internal structure.
Electrodeposition was carried out on mild steel cathodes at 80°C in solutions containing various amounts of sodium tungstate and cobalt sulfate and 0.26mol/l of ammonium tartrate; and further, ammonium hydroxide was added to the solutions to reach pH=8.7 at 30°C.
Two quite individual deposition processes were found under all the conditions applied. That is; the 1st reaction, in the range of from initial deposition potential of the alloy to-900mV (vs. standard saturated calomel electrode), yielded a phase of c.p.h. solid solution deposit containing 0-40 wt.% of W. The 2nd reaction, in the range of more negative side than-900mV, yielded a diffuse pattern deposit containing 51wt.% (25 at. %) of W, which gave extremely diffused X-ray diffraction patterns. In the range of -900- -970mV, the both processes concurrently occurred and mutual interference was observed. The diffuse pattern deposit was assumed to have a structure of highly random aggregates of units consisting of three Co atoms and one W atom.

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