|BAKHTIARINEJAD Arash||Shahid Chamran University|
|Spoluautoři RANJBAR Khalil, ASHRAFI Ali, REZAEI Behzad|
Pitting corrosion Al-5083 has been studied in synthetic sea water at different pH values including 7.5, 8, 8.2 and 8.5. Potentiodynamic polarization and electrochemical impedance spectroscopy has been used in this research. Effect of pH on corrosion potential, corrosion rate, polarization resistance and potential of pitting initiation has been investigated. Rate of initiation of the metastable pits were measured by using the potentiostatic polarization test. Morphology of the samples after the potentiostatic test was investigated using the optical microscopy (OM) and scanning electron microscopy (SEM). Results obtained revealed that, there is a meaningful connection between medium’s pH, pitting potential and metastable pitting rate. Results also revealed that increasing solution’s pH to 8.5 will increase the difference between corrosion potential and pitting potential but variations in metastable pitting rate is not linear.