Anodizing of aluminum under the burning conditions

Abstract The burning anodizing is a separate kind of aluminum electro oxidation observed at the DC voltages quite high to entail the burning of electrolyte at the surface layer without micro-arcs of the growing film. While this phenomenon was observed earlier in the solutions of sulfuric, phosphoric, and carboxylic acids, in this review we aimed to introduce a few other aspects that deserve, in our opinion, particular attention. First, under the burning conditions or close to them, the formation of nanotubed alumina structures dominated the creation of typical densely packed hexagons. Second, these films contained significantly larger amount of incorporated species from the solution. Third, the new exciting properties, such as law band gap and exceptionally high hardness can be bestowed on such alumina coatings. These features seem to be arisen from the compositional hybridization of alumina film upon inclusion of species formed by decomposition of acid anions. In this review, recent advances on the controlled formation and characterization of this material and their possible future applications as well as alternative alumina hybrid coatings are discussed.