The role of Ni content on the stability of Cu–Al–Ni ternary alloy in neutral chloride solutions

The effect of systematic increase of Ni content on the electrochemical behavior of the Cu–Al–Ni ternary alloys in neutral chloride solutions was investigated. Alloys with Ni contents, 5, 10, 30 and 45 mass% were used. The effect of chloride ions on the electrochemical behavior of these alloys was investigated. The presence of Al in the alloy increases its stability. An increase in the nickel content decreases the corrosion rate of the alloys. Conventional electrochemical techniques and electrochemical impedance spectroscopy, EIS, were used. The impedance measurements have shown that the increase of the Ni content and the immersion time of the alloys in the chloride solution increase the corrosion resistance of the alloys. The experimental impedance data were fitted to theoretical data according to a proposed model representing the electrode/electrolyte interface and the equivalent circuit parameters were calculated.