The voltage-time behaviour for porous anodizing of aluminium in a fluoride-containing oxalic acid electrolyte

Citation
A. Mozalev et al., The voltage-time behaviour for porous anodizing of aluminium in a fluoride-containing oxalic acid electrolyte, ELECTROCH C, 3(6), 2001, pp. 299-305
Citations number
22
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
ELECTROCHEMISTRY COMMUNICATIONS
ISSN journal
13882481 → ACNP
Volume
3
Issue
6
Year of publication
2001
Pages
299 - 305
Database
ISI
SICI code
1388-2481(200106)3:6<299:TVBFPA>2.0.ZU;2-7
Abstract
A systematic investigation has been undertaken of voltage-time behaviour fo r galvanostatic porous anodizing of aluminium in 0.4 mol dm(-3) H2C2O4 modi fied by the addition of variable amounts of NH4F. in circumstances of varyi ng current density and stirring conditions. Both the concentration of NH4F in the electrolyte and stirring of the fluoride-containing (FC) electrolyte appeared to affect the voltage-time response for anodizing aluminium, caus ing a dl:crease in the forming voltage. The voltage-reducing effect is furt her substantially enhanced while the solution is stirred. Despite a I:enfol d decrease in the anodizing voltage in the FC electrolyte, no apparent chan ges in pore morphology are determined from SEM observation. The phenomena d escribed are explained by considering formation of FC electrolyte-derived s pecies and their incorporation into growing oxide film. (C) 2001 Published by Elsevier Science B.V.