Degree Of Color Change Research Articles

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A series of comparison tests was carried out on the degree of color change. That is the comparative test of the changing color between the alloys electro-deposited in aqueous solution from five kinds of alloys of In-Pd-Cd system, In-Al-Zn system, In-Cu-Zn system, In-Cu system, and In-Zn-Cd system, and the alloys composed of respective elements. The result is as follows, i) In-Pd-Cd system is the most stable and the color does not change. On this point, much difference between the deposited and alloyed metals is hardly seen.ii) The permissible extent for the composition of Cd and Cu is below 4 percent. If it is over 4 percent, the color of the alloy changes to black.iii) It is most desirable that the permissible extent for Zn is below about 4 to 6 percent in In-Al-Cu-Zn system as for Cd and Cu. Aluminium in the above alloy systems can hardly be deposited by electroplating, therefore, aluminium itself has nothing to do with change of color.iv) When In-Cu sysem and In-Zn-Cd system is used, the degree of change of color depends upon the amount of In added. The more the amount of In increases, the more decreases the degree of change of color.