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In this research, the thickness of the oxide layer and the microhardness of anodized aluminum Al3003 and Al6063 are modeled based on process parameters. To this end, studies of the microhardness and the thickness layer of the anodized surface were made, via techniques of multifactorial analysis and robust design. The following levels of the process parameters were established: temperature [15 °C, 25 °C], time [30min; 60min], electrolyte concentration [1,2M; 2M], current density [1Amp/dm2; 3Amp/dm2], aluminum [Al3003, Al6063], and as a noise parameter, the plastic deformation [0%, 10%, 20%, 30%]. A combined fractional design 27-2 was proposed, based on which a total of 48 tests were performed using sulfuric acid electrolytic solutions. The measurement of microhardness was performed using a Vickers indenter loaded at 400g, and the thickness of the oxide layer was captured using electron microscopy. Variance analysis (ANOVA) was applied to the results in order to determine the significant factors and the robustness of the effects. Results of microhardness [HV] [85,74-308,87]; and the oxide layer thickness [µm] [12,82-94,69] were determined. Finally, the equations for the prediction models are shown for each response as a function of the significant factors, these equations will allow the selection of the microhardness and thickness of oxide layer to fulfill the requirements of a particular product using an appropriate selection of process parameters. [ABSTRACT FROM AUTHOR]

In this research, the thickness of the oxide layer and the microhardness of anodized aluminum Al3003 and Al6063 are modeled based on process parameters. To this end, studies of the microhardness and the thickness layer of the anodized surface were made, via techniques of multifactorial analysis and robust design. The following levels of the process parameters were established: temperature [15°C, 25°C], time [30min; 60min], electrolyte concentration [1,2M; 2M], current density [1Amp/dm2; 3Amp/dm²], aluminum [Al3003, Al6063], and as a noise parameter, the plastic deformation [0%, 10%, 20%, 30%]. A combined fractional design 27-2 was proposed, based on which a total of 48 tests were performed using sulfuric acid electrolytic solutions. The measurement of microhardness was performed using a Vickers indenter loaded at 400g, and the thickness of the oxide layer was captured using electron microscopy. Variance analysis (ANOVA) was applied to the results in order to determine the significant factors and the robustness of the effects. Results of microhardness [HV] [85,74-308,87]; and the oxide layer thickness [µm] [12,82 – 94,69] were determined. Finally, the equations for the prediction models are shown for each response as a function of the significant factors, these equations will allow the selection of the microhardness and thickness of oxide layer to fulfill the requirements of a particular product using an appropriate selection of process parameters. [ABSTRACT FROM AUTHOR]

It is well-known that the geographical situation of the station of natural assays of Cojímar, located in the City of Havana in Cuba, and the variation of their environmental conditions with the time, produce an important influence in the behavior of many metals, especially aluminum anodized and lacquered systems. The present study had the purpose of evaluating the resistance capacity of different variants of structures of anodized and lacquered aluminum of different origins, under the conditions of natural assays. The samples, obtained through different anodized and lacquered technologies, were exposed at the coastal marine atmosphere of the assay station of Cojímar, located on the North coast of Havana City. The samples were carefully observed visually and with a small amplification, after several months of exhibition and the thickness of their anodized and lacquered coat were measured before and after the assays. The gloss of the surfaces was also determined before and after the rehearsal. Bigger affectations were observed in lacquered samples. The importance of the thickness of the protective layer and their impermeabilization grade in the protection capacity of the applied protection system on the aluminum was established, as well as the grade of powder retention of the samples during the experiment. Among the lacquered samples, those of darker tones exhibit greater resistance and the anodized samples experience smaller loss of thickness during the assays. A correspondence between the loss of gloss and the visual observation of the samples was observed. [ABSTRACT FROM AUTHOR]