The investigation for iron electroplating from sulfate baths at 45°C, pH2.2 and without stirring was carried out. From Machu's bath, at high current densities, very lustrous deposits were obtained. The percentage of throwing power was negative and the hardness of deposits increased with current density (above 700VHN at 10A/dm²). It was possible by an appropriate pH control, to keep Fe²⁺ in bath not so remarkably oxidized, and Fe³⁺ formed was gradually reduced to Fe²⁺ with electrolysis and anode dipping. Deposits from the bath containing boric acid, sugar and glycerin were flat, not fully lustrous, and of high hardness. The simple ferrous sulfate bath was easily oxidized and gave soft, gray deposits.

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The purpose of this experiment is to make self fluxing nickel alloy for trial as a basis of eventual industrial production. Alloying elements were charged in a vacuum melting furnace, using Ni-B, Fe-B and metallic boron as boron source.
The melt was cast and then pulverized by atomizing process. The powder was sprayed to the coating 1-1.5mm thick, which was investigated concerning self fluxing, and corrosion and heat resistivity, comparing with the Colmonoy No. 6, Metco 16C and 14C.
The result was as follows:
1) The specimens melted with Fe-B and Ni-B (thermit) were rather difficult in metallizing and its high aluminum content and made its melting point high.
2) The specimens melted with the metallic boron and Ni-B (deoxidization by silicon) were easy in metallizing.
3) With Geiger counter X ray diffractiometer the characteristic lines of CrB, Cr₂B and Cr₃B₄ were observed with all the powders.
4) Corrosion resistivity in HCl and H₂SO₄ acid solution of the metallized specimen is much higher than that of 18-8 stainless steel.

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Effect of the thiourea and its derivatives as well as some surfactants on the formation of bright copper deposits from copper sulfate bath has been studied.
Cathode polarization measurements were carried out in the presence of addition agents and the deposits obtained were analyzed by electron diffraction method and also by photomicroscopy in order to elucidate the characteristics of the crystal structure with respect to the formation of bright deposits.
Addition of brighteners, such as thiourea, acetyl thiourea, allyl thiourea and phenyl thiourea increase the cathode polarization and lead to smooth highly-reflecting surfaces. On the other hand, methyl iso-thiourea, hexamethylene di-thiourea and naphthyl thiourea is found to be ineffective in the formation of bright deposits and generally result in the lower cathode polarization.
Among the surfactants studied, only anionic surfactants, such as Sinto Rex L-100 and Rapisol-80 give the favorable influence on the formation of bright deposits.
It was found that there was no direct relationship between the degree or type of the preferred orientation and the brightness of the deposits.

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Effect of bath temperature, immersion time, and chemical compositions of the base material and molten zinc bath on the thickness of hot dip zinc coating was investigated and the result was as follows:
1) It is already known that the thickness of coating increases with temperature rise and the immersion time at the bath temperature from 430°C to 470°C. Additionally, we found that the thickness of coating increases with the thickness of the base material when the bath temperature and immersion time is constant. When the thickness of base material increases, the thickness of coating acceleratively increases with the rising of the bath temperature and the immersion time.
2) When the bath temperature becomes higher, the thickness of coating acceleratively increases with the immersion time.
3) The thickness of coating increases by adding 13% or 18% chromium to base material, but it decreases by adding 8% nickel.

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