Effect of the anodization conditions on the growth and volume expansion of porous alumina films in malonic acid electrolyte

Abstract

Galvanostatic formation of nanoporous anodic films on aluminum was performed in 0.6 mol•dm− 3 malonic acid electrolyte over a wide current density range in order to define the relationship between the anodizing behavior, oxide growth, dissolution and volume expansion of the oxide. The volume expansion and aluminum dissolution increase with raising the current density, the latter indicating an increasing potential difference across the electrolyte/barrier-layer interface. The same potential difference promotes dissociation of the acid molecules and incorporation of electrolyte-derived species into the film.