Because aluminum has the superior atmospheric corrosion resistance and the oxidation resistance than zinc, we found proper fluxes to hot-dipped aluminum coating and applied protective aluminum coating to steel wires (containing 0.6% carbon), and then researched on the various properties of the coatings; that is, the measurement of the thickness of the alloy layers and pure metal layers by means of microscope, the alkali corrosion test, the measurement of weight of coated metal and the dissolving time of coating in electrolyte, etc.
The procedure of the hot-dipped aluminum coating is similar to that of zinc coating. The experiment was done at 720° and 770°C of metal bath temperature and immersion time in it was 1, 2, 5, 10 and 20 seconds.
We could not found any stable flux in such high temperature above 770° which were possible to use in the preheating lead bath. Accordingly, it is proper to use the molten flux arranging the flux bath in the another place. In those fluxes a molten zinc chloride flux and a molten zinc chloride flux containing 10% lithium chloride are superior in the brightness and smoothness of coating surface. A molten zinc chloride flux containing sodium chloride or ammonium chloride are inferior to the former in the brightness and smoothness. Excess addition of these compound to zinc chloride decreased the fluxing action increasing the viscosity of it.
The thickness of coatin s, the alkali corrosion resistance and weight of coated metal increased with the immersion time and coating bath temperature. But for prevention to decreasing the mechanical properties of coated steel wires, it is necessary that the immersion time is less than 1 or 2 seconds at high temperature such as 770°C and less than 5 seconds at even low temperature such as 720°C.
There is a proportional relation between the thickness of coatings and the dissolving time of coating in electrolyte.

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We researhed the initial wear property of surface-finishing that are influenced by surface-roughness and surface-finishing methods.
Our wear testing machine is designed by Savin's weartesting machine type.
In the case of irregular wear is able to divide the first initial wear term and the second initial wear term. The roughness surface wear greater than the smooth surface when the surface are finished by same method but different finished surface are not.
We consider that the surfaces are found Beilby layer have greater wear-resistance than not found Beilby layer surface, but this consideration needs the more researches.

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Among the finishing of zinc base alloys used for die casting, the electroplating has been applied for general uses. Owing to the intercrystalline corrosion and surface corrosion of zinc alloy die castings, the metal coating must have the thickness sufficient to prevent their corrosion. Therefore, we investigated on the direct nickel plating and copper plating, and we could find that it was necessary to have the thick and compact copper coating, in order to prevent the corrosion and make the mass production.

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