Investigation of corrosion behaviour of CuAlNi alloy in 0.9% NaCl solution

The corrosion behaviour of CuAlNi alloy in 0.9 % NaCl solution at pH = 7.4 and T = 37 °C were studied in still solution and in solution which were stirred with magnetic stirrer. Electrochemical parameters for the CuAlNi alloy were determined using polarization techniques (linear polarization and potentiodynamic polarization) and electrochemical impedance spectroscopy (EIS). The results showed that stirring have negative influence on corrosion stability of CuAlNi alloy and lead to decrease in value of polarization resistance and increase in value of corrosion current density, and also lead to decrease the value of overall impedance of the system. Additionally, the mechanism of corrosion attack developed on the CuAlNi surface was analysed with optical microscopy.