抄録
Etch-pits of various shapes are formed when aluminum is anodically dissolved in chloride solutions. Studies were conducted on predicting by computer simulation the morphology of etchpits formed under various conditions.
A local dissolution model was applied to pit growth in the direction of pit depth, in which it was assumed that active dissolution of Al takes place at the tunnel tip and that the pit wall is covered with passive film. Current density was assumed to be proportional to the growth rate. The computer simulation showed that pit depth increases in temperature, current density, and etching time, and with a decrease in pit diameter.
Aluminum specimens of 99.99% purity were electrolytically etched in HCl solutions, and the empirica results showed good agreement with the simulation. Equally the theoretical growth rate showed good agreement with the empirical rate.
