Abstract
The mechanism of adherence between the deposited zone and the surface of steel plate by the electrophoresis method are not entirely clarified in detail, so the authors intend to clarify these ambiguous points. In this experiment, a colloidal deposit on cathode plate is obtained when the solution which contains 5/1000mol/l AlCl3 in pure alcohol as related in the report 2, are electrolyzed by D.C. with no suspension of Al-powder in the solution. In order to examine if this deposited substance can promote the adherence between Al-powder and steel plate, and to clarify the quality of this deposit, the authors made chemical-, infrared specrum- and X ray-analysises.
Moreover, we examined the influences on depositing rate by the amount of isopropyl alcohol and water which are contained as one of the main component in industrial alcohol employed for the standard suspension.
The results obtained are as follows:
1. It is certified that the colloidal substance which is obtained as deposit on cathode plate by electrolyzing C2H5OH-AlCl3 solution, is Al(OH)3.
2. It seems that the deposited Al(OH)3 will promote the adherence between Al-powder and steel plate.
3. Under high voltage, the decrease of current density of cathode is greatly effected by the increase of resistance of deposited aluminum zone. But, under low voltage, it is more effected by the deposited Al(OH)3. The cathode current density of the industrial C2H5OH-AlCl3 solution is the largest, the suspension of atomized powder is the second and the suspension of flake powder is the smallest.
4. The depositing rate and the amounts of deposit of Al(OH)3 vary with the amount of water in suspension. The former becomes largest with 7% water and the latter with 2-4% water.
5. Whenever the amount of addition of isoprophyl alcohol increases, the deposition rate decreases.
