The anodization of commercially pure Ti alloy (99.5 wt %) and two biomedical titanium alloys, Ti6Al7Nb and Ti6Al4V, was performed, and the resulting anodic oxides were studied. The biomedical alloys were made by Laser Engineered Net Shaping. The glycol-based and glycerol-based electrolytes with 0.3 M ammonium fluoride and 2 wt % of deionized water content were tested. It was found that electrolyte type as well as the chemical composition of the base substrate affected the final morphology and chemical composition of the anodic oxide formed. A higher current density, ionic mobility, and oxide growth rate were obtained in glycol-based electrolyte as compared to those obtained in glycerol-based electrolyte for all tested alloys. A self-organized nanotubular and nanoporous morphology of the anodic oxide in both types of electrolyte was obtained. In each electrolyte, the alloy susceptibility to oxidation increased in the following order: Ti6Al4V < Ti 99.5% < Ti6Al7Nb, which can be correlated to the oxidation susceptibility of the base titanium alloy. It was observed that the more impurities/alloying elements in the substrate, the lower the pore diameters of anodic oxide. There was a higher observed incorporation of electrolyte species into the anodic oxide matrix in the glycerol-based electrolyte compared with that in glycol-based electrolyte@en

Technical purity aluminum was subjected to laser pre-treatment. Subsequently, self-organized anodization in sulfuric acid was performed in order to form nanoporous oxide layer. The influence of the laser pre-treatment operating conditions and grain size of the direct solidified aluminum on the formation of the nanoporous anodic aluminum oxide was studied on the base of FE-SEM images quantitative analyses. It was found there is no significant influence of laser pre-treatment on pore diameter, interpore distance and thickness of the grown oxide. Furthermore, fast Fourier transform-based quantitative image analysis showed that arrangement of the nanoporous alumina grown on the laser pre-treated aluminum is comparable to the arrangement of nanopores formed on high-purity aluminum without any pre-treatment. These findings were supplemented by the circularity analysis of the grown nanopores. This means that laser-treated aluminum elements can be anodized without significant decreases in the quality of the anodic oxides.@en