タングステン表面へのAl₂O₃粒子の電気泳動被覆機構の解析

抄録

Electrophoretic deposition of Al₂O₃ insulation films on tungsten coils was studied by using an in-situ observation technique of the deposition process.
Morphological changes of the gel-like hydroxide deposits that were formed on tungsten coils were studied in relation to the electrolyte content of the water-ethanol suspension medium.
Tungsten surfaces were covered with gel-like deposits containing Al₂O₃ particles immediately when the current was passed between tungsten cathode and pure aluminum anode in the water-ethanol suspension medium containing Al³⁺ and Mg²⁺ ions. The gel-like deposits were hydroxides of Al and Mg. The shape of gel-like deposits covering tungsten coils changed with the content of Al³⁺ and Mg²⁺ ions.
The thickness of the deposit decreased with increasing Al³⁺ ion content and increased with increasing Mg²⁺ ion content of the suspension.