Analysis of Al2O3 Nanostructure Using Scanning Microscopy

It has been reported that the size and shape of the pores depend on the structure of the base metal, the type of electrolyte, and theconditions of the anodizing process. The paper presents thin Al2O3oxide layer formed under hard anodizing conditions on a platemade of EN AW-5251 aluminum alloy. The oxidation of the ceramic layer was carried out for 40–80 minutes in a three-componentSAS electrolyte (aqueous solution of acids: sulphuric 33 ml/l, adipic 67 g/l, and oxalic 30 g/l) at a temperature of 293–313 K, andthe current density was 200–400 A/m2. Presented images were taken by a scanning microscope. A computer analysis of the binaryimages of layers showed different shapes of pores. The structure of ceramic Al2O3layers is one of the main factors determiningmechanical properties. The resistance to wear of specimen-oxide coating layer depends on porosity, morphology, and roughness ofthe ceramic layer surface. A 3D oxide coating model, based on the computer analysis of images from a scanning electron microscope(Philips XL 30 ESEM/EDAX), was proposed