Voltage balance in electrolysis with insoluble anode of various kinds of material was studied. Testing apparatus was consisted of a glass vat for electrolytic cell, an iron plate for cathode, and a graphite-, platinum-, or magnetite-piece for insoluble anode.
The cell voltage and electrode potential according to the change of current density were measured using a valve voltmeter; the resistivity of each anode and specific conductivity of electrolyte using Kohlrausch-bridge.
Furthermore, the behavior of gas polarization on the surface of anode which might have something to do with the electrode potential was observed by microscopy.

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The purpose of the present study was to find out the best conditions for electroplating of aluminum on copper or iron surface, using fused salt bath composed of 60% AlCl₃, 25% NaCl and 15% KCl.
Moreover, the possibility of application of Al frit to the surface of copper or iron aluminum-electroplated under the best conditions was examined.
Result:-
1) It was prerequisite to cover AlCl₃ under the process of fusing with NaCl and KCl, as well as to make pre-electrolysis.
2) As for plating conditions, it was best to keep current density 1.5A/dm² against bath temperature 180°C and bath voltage 0.3V. After plating the plated metal should be immersed in benzene and washed with water.
3) When Al deposit was over 7μ thick, the adhesiveness of Al frit to the Al-plated copper was satisfactory, but that to the Al-plated iron was found to be poor.

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Electrodeposition of Ni-Sn alloy has recently become the object of remarkable attention, for the deposit obtained is of high hardness and has excellent properties such as to prevent corrosion, etc. The structure and properties of this alloy deposit differ from those of the alloy of the same component prepared by casting.
Therefore, a series of experiments to study the effect of heat treatment upon hardness and hardness of the alloy deposit was carried out, and the result was as follows:
1. The component of Ni-Sn alloy deposit obtained from chloride-fluoride electrolyte is around 65% Sn and 35%Ni, and the structure is single phase of solid solution and hexagonal similar to γ (Ni₃Sn₂), while the structure of the alloy of the same component prepared by casting is a mixture of two intermetallic compound γ (Ni₃Sn₂) and δ₁ (Ni₃Sn₄) phase.
2. As plated, the deposit has the (1120) plane parallel to the base metal and the (0002) plane vertical to the base metal corresponds to slip or cleavage plane, along which cracks easily occur or sometimes the deposit is broken.
3. The hardness of the deposit increases by two steps with an increase of temperature of heat treatment.
4. As well as hardness, the structure of the deposit is also affected by heat treatment; at 300°C a part of δ₁ phase precipitates from solid solution and above 700°C it decomposes completely into γ and δ₁ phases.

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