Abstract
Electrophoretic deposition characteristics in aqueous media were investigated at a constant current condition using aqueous alumina suspensions. Apparent deposition rate and green density of deposits were dependent on pH, solid concentration and salt concentration of the suspension. No deposition was observed for the suspension prepared at the isoelectric point of pH 7.9. As the pH of the suspension was adjusted slightly acid from the isoelectric point, the deposition rate rose rapidly. Maximum deposition rate was observed at the pH 7.0. As the suspension became more acid, electrophoretic mobility of alumina particles increased, however, the deposition rate decreased. At a fixed pH, the higher concentration of salt, sodium chloride, gave the smaller amount of deposition and the higher solid concentration gave the larger amount of deposition. Transport number of the surface-charged alumina particles estimated from total electrical current and deposit weight was low.
