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This paper describes the mechanical and corrosion properties of an Al-Fe-Si aluminum alloy containing 0.89 wt. percentage of Fe and 0.15 wt. percentage of Si. These properties are compared to those of aluminum sheets of commercial purity. AA 8079 sheets/foils show higher strength and similar plasticity as A199.7 sheets/foils. Recrystallization response curves of AA 8079 and A199.7 hardened foils show no significant difference between these materials in the sense of the temperatures of beginning and the end of the primary recrystallization. Minimizing of earring for as/rolled and annealed products is made possible by appliance of high degrees of cold rolling deformation ratios in final stages of material processing. Corrosion rates and corrosion currents of AA8079 are higher for 16-20%, and values of polarization resistance are lower by about 14-17%, compared to the A199.7 in both fresh water and 0.51 mol NaCl.

The effect of the chemical composition, i.e. content of silicone (Si) and other alloying elements (Zr, Mn, etc) on the corrosion behaviour and mechanical properties of Al-Mg-Si (6xxx) type alloys was investigated in this paper. Open circuit corrosion potential (OCP) measurements, linear polarization and potentiodynamic anodic/cathodic polarization were employed in order to determine the corrosion behaviour of artificially aged Al-Mg-Si samples in the chloride ions containing aqueous corrosion solutions. The difference in OCPs for the tested 6xxx type alloys in relation to the standard AA1020 alloy was observed to be between 1-4%, except for the AlMg0.65Si0.76Zr0.1 alloy when the difference was 14% (about 100 mV). The presence of zirconium and manganese in AlMgSi0.7 base alloy, that contains small excess of Si, shifts the OCPs to more negative values for -15 mV (~2%) and -88 mV (~11%) in natural water and 0,51 mol NaCl, respectively. All the tested 6xxx type alloys, except AlMg0.7Si1.2Mn0.8, show almost the same corrosion rates and other corrosion characteristics in chloride solution, with mass loss per year between 2.3-3 g/m 2 .

Paper presents the results on the corrosion behavior of some Al-Fe-Si, Al-Mg-Si and Al-Mg-Mn alloys in their final commercially usable tempered state. Durability of alloys was quantified and compared in the sense of corrosion rates in aqueous solutions while also having in mind the role of alloy chemistry. Open circuit corrosion potential (OCP) measurements, linear polarization and potentiodynamic anodic/cathodic polarization was employed in order to determine the corrosion behavior of samples in the mixture of chloride ions containing aqueous corrosion ambient. We found out that AlFe0.83Si0.18(AA8079), AlMg0.63Si0.72 (AA6005) and AlMg4Mn (AA5182) alloy exhibited the highest rates of passivation in 0.51 mol NaCl solution. The group of Al-Fe-Si alloys exhibited the greatest sensitivity to the changes in chemical composition under potentiodynamic polarization. Artificially aged Al-Mg-Si extruded profiles and fully annealed (after cold rolling) Al-Mg-Mn sheets exhibit very similar levels of equilibrium potentials E (I=0) in 0.51 mol NaCl solution. In the case of Al-Fe-Si alloys, we found that Fe/Si ratio also plays an important role, next to the total content of Fe and Si. Alloys with high Fe/Si ratios showed almost 30 % lower polarization resistance compared to the alloys with balanced Fe/Si, even in the case of the equal total content of alloying elements. The AlMg0.7Si1.2Mn0.8 alloy aged after quenching in the sprayed water and AlMg4Zn1.3Mn0.4 annealed sheet exhibit very similar levels of corrosion rates in 0.51 mol NaCl solution.