Abstract
Electrolytic coloring was investigated in the bath containing nickel (II) sulfate, tin (II) sulfate or their mixture by using DC and AC sources. Vertical distribution of the deposited metal in the pores was determined by an electron probe microanalyzer (EPMA). The anodized films were colored in black in all cases and the color tone was depending upon its thickness. Tin was more deposited than nickel in the pores when the same electrolysis duration was used. Deposited nickel and tin were foundto bo located near the pore bottoms and branched pores were observed in the cross sectional figures of the anodized film. It was suggested that the black color of the anodized film was depending not upon the amount of deposited but upon the anodized film structure.
