Nazarov Sh.A., Ganiev I.N., Norova M.T., Ganieva N.I., Calliari I. Potentiodynamic study of the Al + 6% Li alloy doped with yttrium in nacl solution

Abstract

The corrosion and electrochemical behavior of the Al + 6% Li alloy doped with yttrium was studied in a NaCl solution with the help of a potentiodynamic mode of the potentiometric method at a potential scan rate of 2mV • C-1. The relationship between the free corrosion potential and the time of the original Al + 6% Li alloy and yttrium alloys shows a potential shift towards more positive values. At the same time the free corrosion potential of an alloy containing 0.05 wt.% yttrium has a more negative value than the original alloy. Further increase in the yttrium concentration will result in the free corrosion potential shift towards positive values. Yttrium, when added to the Al + 6% Li alloy in the NaCl solution at concentrations of 0.03, 0.3 and 3.0%, causes a shift in the corrosion and pitting potential of alloys into the posi-tive range. The same happens with the repassivation po-tential, which indicates that the pitting centres created have a better passivation in neutral media. With increasing concentration of chloride-ions in the NaCl electrolyte the pitting potential of the Al + 6% Li alloy doped with yttrium shifts into the negative range. An increasing concentration of chloride-ions causes a higher corrosion rate in alloys independent of their com-position. It was demonstrated that the addition of yttrium resulted in an almost twofold lower corrosion rate of the Al + 6% Li alloy in the NaCl solution.

Keywords

Al + 6% Li alloy, yttrium, potentiostatic method, the NaCl electrolyte, corrosion potential, pitting potential, corrosion rate.

Nazarov Shuhratjon Abdugulomovich – Postgraduate Student, Institute of Chemistry named after V.I. Nikitin, Academy of Sciences, Dushanbe, Tajikistan.

Ganiev Izatullo Navruzovich – D.Sc. (Chemistry), Professor, Academic, Academy of Sciences of the Republic of Tajikistan, Head of Laboratory, Institute of Chemistry named after V.I. Nikitin, Dushanbe, Tajikistan.

Norova Muattara Turdyevna – Senior Researcher Institute of Chemistry named after V.I. Nikitin, Academy of Sciences, Dushanbe, Tajikistan.

Ganieva Nargis Izatulloevna – Senior Researcher Institute of Chemistry named after V.I. Nikitin, Academy of Sciences, Dushanbe, Tajikistan.

Irene Calliari – Università degli Studi di Padova, Padova, Italy. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..

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